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Viewed from a neighbouring Pacific island, a huge mushroom cloud expands on the horizon following a nuclear test on Bikini Atoll.
More than 2,000 nuclear tests have been conducted since the invention of the atomic bomb. One of the first was in 1946 on Bikini Atoll in the Pacific Ocean. (© Keystone)

Switzerland advocates for compliance with the non-proliferation norm established by the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The international community has various instruments at its disposal to prevent the proliferation of nuclear weapons. These include the IAEA, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and multilaterally negotiated and applied export controls on nuclear materials. Switzerland is active in all of these areas. 

Export controls and non-proliferation

International Atomic Energy Agency (IAEA)

The IAEA is the world's intergovernmental forum for scientific and technical cooperation in the nuclear field. Its mission is to foster international cooperation to promote the peaceful use of nuclear energy and prevent the misuse of nuclear facilities and materials for military purposes. Its contribution to nuclear non-proliferation is vital.

Under the Treaty on the Non-Proliferation of Nuclear Weapons, all non-nuclear-weapon states must conclude a 'safeguards agreement' with the IAEA. This allows the IAEA to verify that declared nuclear material and facilities are used exclusively for peaceful purposes.

An additional protocol also gives the IAEA the authority to check that states parties do not possess undeclared nuclear material or engage in undeclared nuclear activities. Switzerland has concluded both a safeguards agreement and an additional protocol with the IAEA.

The IAEA also monitors Iran's compliance with its nuclear-related commitments under the Joint Comprehensive Plan of Action (JCPOA) and duties in respect of nuclear safety and security.

Switzerland has been a member of the IAEA since its foundation in 1957 and contributes to the development of nuclear safety and security standards. The Spiez Laboratory and the Swiss Federal Institute of Technology in Lausanne (EPFL) are IAEA Collaborating Centres.

International Atomic Energy Agency

Comprehensive Nuclear-Test-Ban Treaty (CTBT)

Over 2,000 nuclear tests were conducted during the Cold War. Such tests negatively impact people's health, the environment, global security and the non-proliferation architecture. A comprehensive ban on nuclear explosions makes it considerably more difficult to create new or develop existing nuclear weapons. It is thus an essential part of the global non-proliferation regime.

The aim of the CTBT is the verifiable prohibition of nuclear explosions of any kind – in particular nuclear weapons tests – by means of a global monitoring network. The current monitoring network (International Monitoring System) comprises over 300 monitoring stations, which can detect even the smallest explosion in the atmosphere, under water, on land and underground with pinpoint accuracy. The system proved its effectiveness when it detected several nuclear weapons tests conducted by North Korea. Switzerland has a seismic monitoring station in Davos which is part of the international monitoring system.

The negotiations towards the CTBT created a global norm against nuclear testing. Since 1998, all countries except North Korea have observed a moratorium on nuclear testing. However, the treaty itself will not enter into force until specific countries possessing certain nuclear technologies ratify it. Switzerland regularly calls on these states especially to ratify the treaty so that it can rapidly be put into effect.

The tasks of the planned Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), which will be established when the treaty comes into force, are currently carried out by a Provisional Technical Secretariat based in Vienna.

Comprehensive Nuclear-Test-Ban Treaty Organization, CTBTO

Nuclear security and safety

Nuclear security and safety are also integral to Switzerland's efforts to prevent the proliferation of nuclear weapons among state and non-state actors. Nuclear safety guarantees proper operating conditions in nuclear installations to protect people and the environment from harmful radiation. Nuclear security prevents unauthorised actors (such as terrorist groups) from gaining access to nuclear facilities and materials.

Switzerland is an active state party to the Convention on the Physical Protection of Nuclear Material and Nuclear Facilities (CPPNM), for example. This convention aims to prevent, detect and punish theft and other offences involving nuclear materials for civilian use. In 2022, Switzerland co-chairs the Review Conference for the Amended Convention on the Physical Protection of Nuclear Material.

Amendment to the Convention on the Physical Protection of Nuclear Material


Last update 31.01.2022