The status of nuclear weapons

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Facts about nuclear armed states and nuclear weapons worldwide


Gives an overview of nuclear armed states, the number of nuclear warheads worldwide, and international control mechanisms and commitments to disarm. 

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Since 1945, more than 128.000 nuclear warheads have been produced. At the height of the Cold War, there were about 70.000 nuclear weapons stationed around the world. Designed for different deliveries, they were on land, on submarines, on warships and on planes. Following several international agreements to reduce the excessive nuclear arsenals, today there are about 20 – 25.000 nuclear weapons left. The exact figures are not known. Many nuclear weapons are kept disassembled, but thousands are still kept assembled and on high alert, ready to be launched within minutes.


Nuclear weapons were first developed in the USA during the Second World War. Following a single test (16 July 1945), two nuclear bombs were dropped on 6 and 9 August 1945 on Hiroshima and Nagasaki. Estimates vary, but more than 200.000 people were killed, from the shockwave of the initial blast, from burns or from radiation-related injuries.  In 1949, the Soviet Union performed its first test detonation of a nuclear weapon. UK (1952), France (1960) and PR China (1964) followed as the three next NAS.

Today, nine countries are known to be armed with nuclear weapons: USA, Russia, China, France, UK, India, Pakistan, Israel and North Korea. Five more have US nuclear weapons on their soil. These are Belgium, the Netherlands, Germany, Italy and Turkey. USA and Russia still have about 95 % of the total stockpile. Israel neither confirms nor denies that it has nuclear weapons. Nevertheless, it is commonly counted among the nine nuclear armed states (NAS). Four countries had, but no longer have nuclear weapons. These are South Africa, Kazakhstan, Belarus and Ukraine. More than a dozen other countries, including Argentina and Brazil, have had nuclear weapons programmes, but have abandoned them.


No convention so far establishes a categorical ban on use of nuclear weapons. Two international treaties regulate proliferation and testing of nuclear weapons respectively. These are the Non-Proliferation Treaty, which was made international law in 1970, and the Comprehensive Nuclear Test Ban Treaty (CTBT) of 1996, which has yet to enter into force. The NPT is the only legally binding instrument that establishes an obligation for nuclear disarmament (Article VI). Most, but not all NAS are members of the NPT. While NAS who sign and ratify the NPT commit themselves not to assist in the transfer of nuclear weapons to non-NAS, the latter commit themselves not to acquire nuclear weapons. Of the four states who have acquired nuclear weapons after 1970, three were never members of the NPT (India, Pakistan and Israel), while the fourth (North Korea) withdrew in 2003. India and Pakistan both demonstrated their nuclear capacity in tests in 1998. (India also in 1974). North Korea tested in 2006, 2009, and 2013. Any Israeli nuclear tests are disputed.


In addition to NPT and CTBT, the main treaties regulating nuclear weapons are the several self-declared nuclear weapon free zones (NWFZ) that exist around the world. (See separate ILPI fact sheet). More than 50 % of the Earth’s surface now comprises NWFZ, including 99 per cent of all land in the southern hemisphere. All of Africa and all of Latin America and the Caribbean are NWFZs. Other NWFZs can be found in the South Pacific, Antarctica, Southeast Asia and Central Asia. Mongolia is also a declared NWF state. NWFZs prohibit the development, acquisition, placement, testing and use of nuclear weapons. They do not prohibit the development and use of nuclear energy, but ban dumping of nuclear waste.

To view the Nuclear-weapon-free zones treaty texts, click here.