One night in Bangkok

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An overview of the history and politics of nuclear non-proliferation and disarmament in Southeast Asia.

23 November 2016


This article provides an overview of the history and politics of nuclear non-proliferation and disarmament efforts in Southeast Asia, exploring, in particular, the establishment of the Southeast Asia nuclear-weapon-free zone (SEANWFZ). The paper also considers the role of Southeast Asian states in the humanitarian discourse on nuclear disarmament and in international efforts to prohibit and eliminate nuclear weapons.



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No Southeast Asian state has ever developed nuclear weapons and all Southeast Asian states are fully compliant parties to the Nuclear Non-proliferation Treaty (NPT).[1] As a supplement to their obligations under the NPT, the ten states that make up the Association of Southeast Asian Nations (ASEAN) have also established a comprehensive regional legal ban on nuclear weapons – the Southeast Asia Nuclear-Weapon-Free-Zone Treaty (SEANWFZ). The SEANWFZ entered into force in 1997, consolidating its parties’ commitment to remain nuclear-free and to work collectively for the achievement of a world without nuclear weapons. Over the years, several countries in the region have engaged actively in nuclear disarmament initiatives and continue to play key roles in multilateral nuclear disarmament efforts. More recently, Southeast Asian states have been vocal supporters of the humanitarian approach to nuclear disarmament, arguing strongly for the prohibition and elimination of nuclear weapons worldwide.

This background paper outlines the history of nuclear non-proliferation and disarmament policy in Southeast Asia. Exploring the role of Southeast Asian states in efforts at creating a world free of nuclear weapons, the paper analyses the process that lead to the establishment of the SEANWFZ, as well as on-going efforts at creating a global ban on nuclear weapons.asean-summit

The Treaty of Bangkok

The Southeast Asia Nuclear-Weapon-Free-Zone Treaty (SEANWFZ), also known as the Treaty of Bangkok, was signed on 15 December 1995 in Bangkok. The Treaty was signed by Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam and entered into force on 27 March 1997.[2] The first formal discussions of a SEANWFZ date back to 1971, when the original five members (Indonesia, Malaysia, the Philippines, Singapore and Thailand) of the Association of Southeast Asian Nations (ASEAN) signed a declaration on a Zone of Peace, Freedom, and Neutrality (ZOPFAN).[3]

None of the current ASEAN member states has ever possessed nuclear weapons, and a majority of the states in the region condemned nuclear weapons before any concrete proposals for a nuclear-weapon-free zone (NWFZ) were advanced.[4] However, in the mid-1960s, Indonesia’s President Sukarno seriously considered initiating a nuclear-weapons programme, announcing that, “God willing, Indonesia will shortly produce its own atom bomb”.[5] Yet as it turned out, Indonesia refrained from developing nuclear weapons, and instead joined the Nuclear Non-Proliferation Treaty (NPT) in 1970 as a non-nuclear-weapon state.

Arising as a response to widespread concerns about the five original nuclear-weapon states’ (NWS) military bases and nuclear transits through the region, the establishment of a Southeast Asia NWFZ was the first major initiative of the ZOPFAN. Noting the establishment of a NWFZ in Latin America and the Caribbean (1968), as well the proposal for an African NWFZ, a Southeast Asian NWFZ was seen as a means of ensuring the peace and stability of the region. However, regional conflicts caused difficulties for the ZOPFAN initiative. In particular, the Vietnamese invasion of Cambodia in 1979 led to heightened tensions in the region, souring the political climate. ASEAN suspended the NWFZ initiative shortly after the Vietnamese invasion.

Due to the perceived threat from Vietnam, ASEAN members sought strategic support from both the United States and China, aiming to isolate Vietnam politically while trying to negotiate a settlement to the Cambodian conflict. Yet despite – or perhaps as a result of – the unfavourable political environment, several ASEAN members saw a Southeast Asian NWFZ as an important initiative and means of bolstering ZOPFAN. During the 1970s and 1980s, Indonesia and Malaysia were the chief advocates inside ASEAN of a NWFZ, formally presenting the proposal for a SEANWFZ to a meeting of the foreign ministers of the ASEAN members in Jakarta in 1984. Two years later the ministers established a committee of officials working on ZOPFAN, authorising them to start the preliminary drafting of a nuclear-weapon-free zone treaty.[6]

External opposition

The United States (US) quickly raised objections to the proposed treaty. The Americans’ main concern was that if Western-leaning Southeast Asian states such as the Philippines and Thailand joined the treaty, but not Soviet-aligned Vietnam, the Soviets would gain a clear advantage in the region by being able to station nuclear weapons in Vietnam without the United States having an opportunity to respond in kind. As a direct consequence of the US’ objections, three pro-Western countries in the region – Thailand, the Philippines and Singapore – refused to continue negotiations towards a treaty.[7]

Post-Cold War revival

When the Cold War ended and the Cambodian conflict came to an end with the signing of the Paris Peace Agreement on Cambodia in 1991, the prospects for the SEANFWZ increased markedly. Improvements in the relationship between Vietnam and ASEAN removed a considerable obstacle to cooperation between the neighbours. The reduced military presence of the Cold War superpowers also increased the prospects of the zone.[8] Over the course of 1991 and 1992, the US discontinued its naval and air bases in the Philippines. The Russian Federation, for its part, maintained a naval base in Vietnam until 2002, but withdrew most of its personnel and vessels in the early 1990s.[9]

The decision made by ASEAN in 1992 to begin engaging in regional security issues enabled the process of establishing a NWFZ to move forward. Although there was no immediate danger of nuclear proliferation within Southeast Asia at that time, ASEAN members were worried about China’s expanding nuclear arsenal and a resurgence of territorial disputes in the South China Sea. There was also a concern that North Korea’s nuclear programme might influence Japan to develop nuclear weapons, which, in turn, could lead to a domino effect of nuclear proliferation in the Asia–Pacific. A NWFZ covering both the land mass and maritime zones of Southeast Asia was seen as a tool to ensure the security and continued denuclearization of the region.[10]

At the ASEAN ministerial meeting in Singapore in 1993, ASEAN foreign ministers reaffirmed their commitment to ZOPFAN and agreed to finally establish a NWFZ.

At the ASEAN ministerial meeting in Singapore in 1993, ASEAN foreign ministers reaffirmed their commitment to ZOPFAN and agreed to finally establish a NWFZ. At the fifth ASEAN summit on 15 December 1995, the Treaty of Bangkok was signed by representatives of all six ASEAN members as well as Vietnam, Cambodia, Laos, and Myanmar, which were non-member observers of ASEAN at the time.[11] The Treaty entered into force on 28 March 1997. The SEANWFZ became fully effective when the Philippines ratified the Treaty on 21 June 2001. Compared to other NWFZs, the process from the date of signature to the date of entry into force proceeded rapidly.

The terms of the Treaty

The Treaty of Bangkok establishes the same key prohibitions as the two NWFZ treaties that preceded it: the Treaty of Tlatelolco (Latin America and the Caribbean) and Treaty of Rarotonga (the South Pacific). The states parties of the SEANWFZ are obligated not to

  • develop, manufacture or otherwise acquire, possess or have control over nuclear weapons;
  • station or transport nuclear weapons by any means;
  • test or use nuclear weapons anywhere inside or outside the zone;
  • allow or take any action to assist or encourage the development, manufacture, testing, stationing or acquisition of nuclear weapons;
  • dump radioactive material or waste within the zone or allow any other state to do so;
  • seek or receive any assistance in the above.

By prohibiting the transport of nuclear weapons by any means within the entire zone, including the continental shelf and exclusive economic zone (EEZ), the SEANWFZ Treaty goes further than the treaties of Tlatelolco and Rarotonga. The Treaty of Tlatelolco does not include a prohibition on the transportation of nuclear weapons within the zone at all, whereas the Treaty of Rarotonga limits its prohibition of transport of nuclear weapons to land and inland waters.

While the SEANWFZ Treaty includes an explicit reference to the continental shelves and EEZ, the treaties of Tlatelolco and Rarotonga do not. However, the latter treaties’ failure to mention the continental shelves and EEZ explicitly does not necessarily suggest that these areas are excluded from the respective zones. The Treaty of Tlatelolco defines the zonal area to “include the territorial sea, air space and any other space over which the State exercises sovereignty in accordance with its own legislation”,[12] and the Treaty of Rarotonga defines the zone to include “internal waters, territorial sea and archipelagic waters, the seabed and subsoil beneath, the land territory and the airspace above them”.[13]

The rules on the law of the sea, including the terms used above, are defined in the United Nations Convention on the Law of the Sea of 1982.[14] The Treaty of Bangkok states clearly that “Nothing in this Treaty shall prejudice the rights or the exercise of these rights by any State under the provisions of the United Nations Conventions on the Law of the Sea of 1982, in particular with regard to freedom of the high seas, rights of innocent passage, archipelagic sea lanes passage or transit passage of ships and aircraft”.[15] In addition to the definitions above, the Treaty of Tlatelolco and the Treaty of Rarotonga define their zone’s territory in detail in latitudes and longitudes.[16] According to the maps drawn based on this information, the difference with regard to geographic scope among these three NWFZs seem minor.

The Treaty of Bangkok states clearly that ‘Nothing in this Treaty shall prejudice the rights or the exercise of these rights by any State under the provisions of the United Nations Conventions on the Law of the Sea’.

The inclusion of the continental shelves and the EEZs of the States Parties were added in the third draft of the Bangkok Treaty in early 1993 for the purpose of protecting the Southeast Asian region from the possible dumping of radioactive material or wastes at sea. Some nuclear-weapon states have argued that the Seabed Arms Control Treaty of 1971 provides sufficient guarantees that the region’s continental shelves would be free of nuclear weapons and other weapons of mass destruction (WMD).[17] The Seabed Treaty bans the emplantation and emplacement of nuclear weapons or WMDs on the seabed and the ocean floor, and in the subsoil thereof beyond the outer limit of a sea-bed zone, as well as structures, launching installations or any other facilities specifically designed for storing, testing or using such weapons.[18] However, the Seabed Treaty was limited to banning the emplacement of nuclear weapons or other WMDs – not radioactive material or wastes.[19]

Article 4 of the SEANFWZ Treaty acknowledges the parties’ right to the use of nuclear energy for peaceful purposes, and urges the states parties to act in accordance with the guidelines and standards determined by the International Atomic Energy Agency’s (IAEA) safeguards system. According to Article 5 of the Treaty, each State Party must conclude a safeguards agreement with the IAEA no later than eighteen months after the entry into force for that State Party of the Treaty.

The SEANWFZ Treaty also establishes a Commission to oversee the implementation of the Treaty. All states parties are members of the Commission, constituted by the parties’ foreign ministers, their representatives and advisors. The Commission meets as and when necessary in accordance with the provisions of the Treaty, including upon the request of any state party, and as far as possible the Commission shall meet in conjunction with the ASEAN Ministerial Meeting.[20] In addition, the Treaty establishes an Executive Committee as a subsidiary organ of the Commission, in which each State Party is a member and shall be represented by one senior official, who may be accompanied by alternates and advisers. The Executive Commission ensures that the verification measures outlined in the control system of Article 10 of the Treaty are being carried out properly, including the authorization of fact-finding missions.[21]

Protocol to the Treaty

Following the pattern of the Tlatelolco and Rarotonga treaties, the SEANWFZ Treaty includes a protocol open for signature by the five nuclear-weapon states (NWS) as defined by the NPT: China, France, Russia, the United Kingdom and the United States. Under the SEANFWZ Protocol, each of the NWS undertakes to respect the SEANWFZ Treaty.[22] Furthermore, each of the NWS would undertake not to use or threaten to use nuclear weapons against any state party to the Treaty, and, additionally, not to use or threaten to use nuclear weapons within the zone.[23]

So far, none of the five NWS have signed the Treaty Protocol. Their main objection has been the inclusion in the zone of the respective states’ continental shelves and the EEZs, which they argue undermines the principle of freedom of movement in the high seas as codified by the 1982 UN Convention on the Law of the Sea.[24] The NWS have also raised the issue that the continental shelves and EEZs are not clearly defined, creating uncertainty over the geographical scope of the Treaty.[25]

In 1997, then US Presidential Special Representative for Arms Control, Non-Proliferation and Disarmament, Ambassador Thomas Graham, said the SEANWFZ Treaty “could create an ‘unfortunate precedent’ that undermines the US interpretation of maritime law”.[26] According to the US, the inclusion of the continental shelves and EEZs violates the Law of the Sea which allows the coastal states to exercise sovereign rights over resources in EEZ and continental shelves, but not the exercising of political rights, referring in particular to the prohibition on transit of nuclear weapons within the treaty zone. The US has also voiced concerns that the Treaty’s provisions about the rights of innocent passage of warships and aircraft are “too restrictive”.[27]

There have been consultations between the states parties to the Treaty and the NWS for more than a decade concerning the NWS’ accession to the Protocol to the Treaty. The SEANFWZ Parties have repeatedly called for the NWS to sign the Protocol. Some progress has been made over the years. In 2010, the then US Secretary of State Hilary Clinton announced that the US was prepared to consult with SEANWFZ Parties in order to reach an agreement regarding the Treaty protocol.

Russia has expressed a positive attitude towards the Treaty, but stated that it needed some clarifications about the Treaty’s geographic scope and the rights of passage in the Treaty zone. Despite the positive attitude, Russia’s signature to the Protocol has not materialised.[28]

Noting that only a few “‘technical details’ remained to be sorted out”, France expressed its willingness to sign the Protocol in early 1996. Just prior to this, France had completed its sixth and hitherto final nuclear test in the South Pacific, and declared its intention to sign the Rarotonga Treaty Protocol. But France has yet to sign the SEANFWZ Protocol.[29]

China has been particularly concerned about the implications of the Treaty on the question of sovereignty in the South China Sea. Having resolved the differences between China and the SEANWFZ states parties on this issue in the early 2000s, China publicly announced its readiness to sign the protocol in 2004. Subsequent disputes in the South China Sea have since set the process back anew.

In November 2011, the United Kingdom issued a statement from the Foreign Secretary declaring that “After over ten years of negotiations, a process for P5 (China, France, Russia, the UK and US) signature of the Protocol to the Southeast Asian Nuclear Weapons Free Zone Treaty has been agreed”.[30] Yet this process has not resulted in any results with regard to signatures.

At the 20th ASEAN Summit in July 2012, it was expected that the meeting would end with the signing of the ASEAN Statement on the Protocol to the Treaty of the SEANWFZ, agreement on a Memorandum of Understanding between ASEAN and China on the protocol and the treaty to the SEANWFZ, and the signing of the Protocol by the five NWS. However, due to reservations by four of the NWS (France, Russia, United Kingdom and the US), the SEANWFZ Commission decided to postpone the signings to have more time to review the text. The SEANWFZ Commission also decided to postpone the signing of a Memorandum of Understanding between China and ASEAN because of the unresolved matters with the four other NWS.[31]

At the NPT Preparatory Committee in 2014, both France and the United States stated their readiness to sign the SEANWFZ Protocol.[32] This was reiterated by the United Kingdom, on behalf of the P5, at the NPT Review Conference in 2015: “We note that consultations also continue with the State Parties to the Southeast Asia Nuclear-Weapon-Free Zone (SEANWFZ) Treaty and encourage the Parties to that Treaty to continue to engage constructively in order to find solutions to outstanding issues. We remain ready to sign the SEANWFZ Protocol.”[33] But the SEANFWZ Protocol was still not signed.

As the SEANWFZ parties continue to call on the NWS to sign the Protocol,[34] the inclusion of the continental shelves and EEZs in the zonal area remains the main obstacle for four of the NWS (France, Russia, United Kingdom and the US) to sign it. And although most SEANWFZ states voice concern about the NWS’ reluctance to sign the Protocol, the parties diverge considerably in their assessments of the urgency of securing the NWS’ signatures. While smaller Southeast Asian states generally put this high up on their priority lists, some of the larger states in the region seem reluctant to pressurise the NWS to sign the protocol.

At the 2015 ASEAN Summit in Malaysia, Myanmar’s foreign minister sought to make the lacking signatures a priority, but was met with disinterest by the other states parties. Instead of intensifying efforts to urge the NWS to sign the protocol, the SEANWFZ Commission “was still reviewing the reservations expressed by France, Russia, and the United Kingdom.”[35] However, it is worth noting that the accession of the five NWS to the Protocol will most likely have a minor impact on the zone as such, in particular because the protocol only addresses five out of nine countries known or widely considered to possess nuclear weapons, leaving out India, Pakistan, Israel and North-Korea.


The role of Southeast Asia in global disarmament efforts

The preamble of the Treaty of Bangkok makes clear that the Treaty is not limited to denuclearization of Southeast Asia but that the parties are “[d]etermined to take concrete action which will contribute to the progress towards general and complete disarmament of nuclear weapons”. However, the approach to and involvement in global disarmament initiatives of ASEAN member states has varied considerably over the years.

The Non-Proliferation Treaty and the Conference on Disarmament

All of the ASEAN members have ratified the Non-Proliferation Treaty (NPT), considered to be the cornerstone of the global nuclear non-proliferation and nuclear disarmament regime. Four of the parties to the SEANWFZ Treaty are also members of the Conference on Disarmament (CD): Indonesia, Malaysia, Myanmar and Vietnam.[36] Additionally, Brunei, Laos, the Philippines, Singapore and Thailand are part of the informal group of observer states to the CD (IGOS), a group of states that advocate for the expansion of the membership of the CD. Currently, the CD only has 65 member states, and with no elections or rotation system many argue that the CD is a poor representation of the interests of the international community.

The Non-Aligned Movement

All of the ten ASEAN members are also members of the Non-Aligned Movement (NAM), regularly participating in NAM meetings and supporting the group’s statements in various disarmament bodies. The NAM has a working group on disarmament, which, for most of its history, has been coordinated by Indonesia.[37] Speaking on behalf of the NAM in the First Committee at the United Nations General Asembly (UNGA) in 2015, Indonesia’s Vice Minister of Foreign Affairs voiced support for the conclusion of a comprehensive convention on nuclear weapons, and recalled the General Assembly’s decision “to convene, no later than 2018, a UN high level conference to review progress made in this regard.” [38]

All of the ten ASEAN members are also members of the Non-Aligned Movement (NAM).

The NAM has called for the elimination of nuclear weapons in several global disarmament bodies over the last years. At NAM’s XVI Ministerial Conference and Commemorative Meeting in May 2011, the group issued a statement calling for the total elimination of nuclear weapons based on “their deep concern at the threat to humanity posed by the continued existence of nuclear weapons and of their possible use or threat of use”.[39] This concern was reiterated at the 2015 NPT Review Conference, where they argued that “any use or threat of use of nuclear weapons would be a crime against humanity and a violation of the principles of the Charter of the United Nations and international law, in particular international humanitarian law.”[40] It is worth noting that the majority of the NAM states are members of a nuclear-weapon-free zones, but also that three of the members possess nuclear weapons (India, Pakistan and North-Korea).

The Malaysia-resolution

An important arena for discussing nuclear disarmament is the UNGA First Committee, one of six main committees at the UNGA. The First Committee is responsible for disarmament and related international security issues and is open for all UN member states. For many years, Malaysia and Costa Rica have been flag-bearer for a call to start negotiations on a comprehensive nuclear weapons convention that would prohibit the use, threat of use, possession, development, testing, deployment and transfer of nuclear weapons, and provide for a phased programme for the elimination of all nuclear weapons under effective international control.

The ‘Malaysia-resolution’ was submitted to the UN General Assembly (First Committee) for the first time in 1997, and has since then been adopted by the UNGA on an annual basis.

The ‘Malaysia-resolution’ was submitted to the UN General Assembly (First Committee) for the first time in 1997, and has since then been adopted by the UNGA on an annual basis. In 2007, Malaysia and Costa Rica also formally submitted a ‘model’ nuclear weapons convention to the General Assembly.[41] Critics have advanced that the presentation of a ready-made draft of a treaty might not be the approach most conducive to the actual start of negotiations on such an instrument. This is a view that has also been reflected in the explanations of votes by some of the UN member states. Another critique has been that the resolution has called for negotiations to take place in the CD, which has been deadlocked since the Malaysia-resolution was first introduced. All ASEAN countries are co-sponsors of the resolution, along with a number of other NAM countries.

The Comprehensive Test-Ban Treaty (CTBT)

The Comprehensive Test-Ban Treaty (CTBT) bans the physical testing of nuclear weapons in all environments. The Treaty was negotiated in the CD in Geneva, but was adopted by the General Assembly because the CD could not reach consensus. The CTBT was opened for signature in 1996, and currently has more than 159 parties. Still, the treaty has not yet entered into force, since entry into force requires that all the states listed in the second annex of the treaty (‘nuclear capable states’) ratify it. There are currently eight such ratifications missing. As of November 2016, all ASEAN countries but Thailand have ratified the CTBT.[42] Indonesia ratified the Treaty in 2012, and, being an “Annex 2” country, Indonesia’s ratification was important. Indonesia delayed its ratification of the CTBT explicitly because of the United States’ refusal to ratify, but eventually reversed its opposition even though the US still has not ratified.[43]

Myanmar is the latest ASEAN state to ratify the CTBT, completing its ratification process in New York on 21 September 2016. Although not an “Annex 2” state, Myanmar’s ratification may have symbolic effects.

Myanmar is the latest ASEAN state to ratify the CTBT, completing its ratification process in New York on 21 September 2016.

As Lassina Zerbo, Executive Secretary of the CTBTO stated upon Myanmar’s ratification: “State Counsellor Aung San Suu Kyi has sent a clear signal today that Myanmar supports nuclear disarmament and non-proliferation. It is also fitting that a Nobel Peace Prize laureate should deposit the ratification instrument – a first for the Treaty”.[44] As the only ASEAN state yet to ratify CTBT, Thailand remains, however, at least nominally supportive of the treaty, “firmly committed to ratify the CTBT at the earliest opportunity”.[45]

The Humanitarian Initiative

Over the last couple of years there has been a shift in the multilateral debate on nuclear disarmament, away from a conventional arms control discourse towards a stronger focus on the humanitarian consequences of nuclear weapons. This shift can be seen both within the established disarmament bodies, like the NPT and the UNGA First Committee, and outside.

In November 2011, the Red Cross/Red Crescent movement made an important contribution to this discursive shift by adopting a historic resolution on the humanitarian impact of nuclear weapons, in which they called for the prohibition and elimination of all nuclear weapons.[46]

In May 2012, 16 states made a first joint statement on the “humanitarian dimension of nuclear disarmament” at the NPT Preparatory Committee (PrepCom) meeting, arguing that any use of nuclear weapons would have catastrophic humanitarian consequences, and that nuclear weapons therefore should not be used under any circumstances. [47] From Southeast Asia, Indonesia, Malaysia and the Philippines supported the statement. A similar statement was given by Switzerland on behalf of 34 states at the nuclear weapons debate in the First Committee of UNGA in October 2012. [48] In addition to the three above-mentioned Southeast Asian states, Thailand also joined this statement. At the NPT PrepCom in Geneva in April 2013, South Africa delivered a joint statement on behalf of 80 states on the catastrophic humanitarian consequences of nuclear weapons. This time, Cambodia and Singapore also supported the statement.[49] In both 2013 and 2014, New Zealand delivered the joint statements on humanitarian consequences to the UNGA First Committee. At the 2013 session, 125 states joined the humanitarian statement, with Laos, Myanmar, Timor-Leste, and Vietnam adding their voices to the Southeast Asian chorus. [50] Brunei joined the joint statement at the 2014 session of the UNGA, when the total number increased to 155, making Southeast Asia united in warning against the humanitarian consequences of nuclear weapons. [51] All of the Southeast Asian states joined the final humanitarian consequences statement delivered by Austria’s at the 2015 NPT Review Conference. [52]

hinw-boxFollowing this, there have been six joint statements on this issue in the contexts of NPT and UNGA.

With the exception of Cambodia and Singapore, all ASEAN countries were present at the Oslo Conference in 2013.

The humanitarian initiative was also brought forward at three ad hoc international conferences. In March 2013, aiming to provide an arena for a fact-based discussion of the humanitarian and developmental consequences of a nuclear weapon detonation, the Norwegian government hosted an international conference on the humanitarian impact of nuclear weapons. With nearly 130 states participating, as well as several UN organisations, the International Red Cross movement and representatives of civil society, the conference firmly established the humanitarian perspective as an important entry-point to nuclear disarmament discussions.

With the exception of Cambodia and Singapore, all ASEAN countries were present at the Conference. Malaysia and the Philippines made individual statements during the working sessions. Before the conference closed, Mexico offered to host a follow-up conference in order to keep the humanitarian discourse moving. This conference was held in Nayarit in February 2014, and included the same Southeast Asian states that attended the conference in Oslo.

At the following conference, in Vienna, in December 2014, Singapore also joined, leaving Cambodia as the only non-participating state from South-East Asia. At the end of this conference, Austria delivered a pledge to “fill the legal gap for the prohibition and elimination of nuclear weapons.”[53] All of the Southeast Asian states, bar Myanmar, have formally endorsed this “Humanitarian Pledge”. When the Pledge was voted upon as a UNGA resolution in 2015, however, all of the Southeast Asian states, including Myanmar, voted in favour.


The major conflicts that took place in Cambodia, Laos and Vietnam in the late 1960s and early 1970s bear evidence of the potential for conventional wars to escalate. The fear of use of nuclear weapons in such situations has generated continued interest in regional denuclearization.[54] The idea of a Southeast Asia nuclear-weapon-free zone dates back to the early 1970s, but due to an unfavourable political environment in the region during the 1970s and 1980s, the idea was not realized until after the end of the Cold War. The change in the political environment combined with the closing of foreign military bases in the region, as well as changes within ASEAN, enabled the establishment of the Southeast Asian NWFZ in 1995.

The humanitarian approach to nuclear disarmament has created a new momentum for nuclear disarmament. With three international conferences, six joint statements at various disarmament fora, and several UNGA resolutions, the humanitarian initiative has gained a foothold in the world of disarmament. Southeast Asian states have been at the forefront of this initiative.

As the permanent representative of Myanmar to the United Nations argued, on behalf of ASEAN at the 2015 NPT Review Conference: “Our efforts to achieve nuclear disarmament will be challenging, but we believe that the goal of achieving nuclear disarmament is possible when concrete and practical steps to dismantle the world’s remaining nuclear weapons are implemented, as soon as possible, and in a transparent, irreversible and verifiable manner.” One such step is the movement towards the negotiation of a ban nuclear weapons. Based on the report of a UN Open-Ended Working Group on nuclear disarmament that met in Geneva over three sessions in 2016 – chaired by Thailand’s UN Ambassador Thani Thongphakdi – the UNGA decided, in the fall of 2016, to convene a conference in 2017 to negotiate a treaty banning nuclear weapons.

The humanitarian approach to nuclear disarmament has created a new momentum for nuclear disarmament.

Southeast Asian states were instrumental in securing this mandate, and they are likely to continue to play important roles in the process towards a global ban treaty, and, eventually, a world without nuclear weapons.


[1]        Southeast Asia consists of the countries that are geographically located south of China, east of India, west of New Guinea and north of Australia: Brunei, Burma, Cambodia, Timor-Leste, Indonesia, Laos, Malaysia, Philippines, Singapore, Thailand, and Vietnam. All but Timor-Leste are also members of the Association of Southeast Asian Nations (ASEAN).

[2]       The Treaty was ratified by Brunei on 22 November 1996, Cambodia on 27 March 1997, Indonesia on 10 April 1997, Laos on 16 July 1996, Malaysia on 11 October 1996, Myanmar on 17 July 1996, the Philippines on 21 June 2001, Singapore on 27 March 1997, Thailand on 20 March 1997, and Vietnam on 26 November 1996.

[3]       The 1971 Zone of Peace, Freedom and Neutrality Declaration was signed on 27 November 1971.

[4]       Cornellier, Erik A. (2003), In the Zone: Why the United States should sign the protocol to the Southeast Asia Nuclear-Weapon-free zone, Pacific Rim Law & Policy Journal, 12 (1): 244.

[5]       Lieggi, Stephanie (2012), “The Nonproliferation Tiger: Indonesia’s Impact on Nonproliferation in Asia and Beyond”, Monterey Institute of International Studies, available at: (Accessed 27.05.2013).

[6]       Cornellier 2003: 246; Acharya, Amitav and Sola Ogunbanwo (1998), “The Nuclear Weapon-Free Zones in South-East Asia and Africa”, in SIPRI Yearbook 1998, Oxford: Oxford University Press, pp.443-455, first half of article available at: (Accessed 24.05.2013); Pande, Savita (1998), ”Prospects of nuclear weapon-free zones: South-East and central Asia”, Strategic Analysis, 22 (6), pp. 855-866: 855.

[7]       Acharya 1998: 444.

[8]       “Southeast Asia Nuclear-Weapon-Free Zone Treaty (Treaty of Bangkok)”, James Martin Center for Nonproliferation Studies (CNS), last updated 28.01.2013, (Accessed 26.04.2013); Hamel-Green 2011: 7.

[9]       In late 2012 it was known that the US would return to Subic Bay, which has a port and an airfield now known as Subic Bay Freeport Zone, and use Subic Bay to host US ships, marines and aircraft on a semi-permanent basis. This implies that there are no plans to reopen a permanent US base in the Philippines.

[10]      Acharya 1998: 444.

[11]       Acharya 1998: 444; CNS 2013: 1.

[12]      Treaty of Tlatelolco:

[13]      Treaty of Rarotonga:

[14]      United Nations Convention on the Law of the Sea:

[15]      Article 2 (2), Southeast Asian Nuclear Weapons Free Zone Treaty.

[16]      Article 4 (2), Treaty of Tlatelolco; Annex 1, Treaty of Rarotonga.

[17]      Abad, M.C. Jr (2005), ”A Nuclear Weapon-Free Southeast Asia and its Continuing Strategic Significance”, Contemporary Southeast Asia, 27 (2), pp. 165-187: 181–2.

[18]      Article I, Treaty on the prohibition of the emplacement of nuclear weapons and other weapons of mass destruction on the sea-bed and the ocean floor and in the subsoil thereof (Seabed Treaty), available at: (Accessed 05.06.2013)

[19]      Abad 2005: 182.

[20]      Article 8, Southeast Asian Nuclear Weapons Free Zone Treaty

[21]      Article 10, Southeast Asian Nuclear Weapons Free Zone Treaty.

[22]      Article 1, Protocol to the Southeast Asian Nuclear Weapons Free Zone Treaty.

[23]      Article 2, Protocol to the Southeast Asian Nuclear Weapons Free Zone Treaty.

[24]      Crail, Peter and Xiaodon Liang (2012), “Southeast Asia Nuclear-Weapons-Free Zone and the Nuclear-Weapon States”, Asia Pacific Bulletin, Number 148, February 7.

[25]      CNS 2013: 2.

[26]      Crail and Liang 2012: 1.

[27]      Acharya 1998: 446.

[28]      Acharya 1998: 447.

[29]      Ibid.

[30]      “Foreign Secretary statement on Nuclear Weapon Free Zone Treaty” (2011), available at: (Accessed 27.05.2012).

[31]      “Signing of anti-nuke pacts postponed” (2012), Manila Times, available at: (Accessed 27.05.2013); CNS 2013.

[32]      “PrepCom 2014”(2014), available at: (Accessed 24.10.2016).

[33]      “Statement by the People’s Republic of China, France, The Russian Federation, The United Kingdom of Great Britain and Northern Ireland, and The United States of America to the 2015 Treaty on the Non-Proliferation of Nuclear Weapons Review Conference” (2015), available at (Accessed 24.10.2016).

[34]      “OUR PEOPLE, OUR COMMUNITY, OUR VISION” (2015), available at:

[35]      Dalpino, Catharin and Timothy Westmyer (2016), “Southeast Asia: A Measured Nuclear Policy,” in Mouchizuki, Mike M. and Deepa M. Ollapally (eds) Nuclear Debates in Asia: The Role of Geopolitics and Domestic Processes (pp. 185-220) Rowman & Littlefield: London.

[36]      The CD was established in 1978 as a permanent multilateral negotiation forum for disarmament affairs.

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