FAQ on Ukraine and Nuclear Weapons


Many have questions about the former stationing of Soviet nuclear weapons on Ukrainian territory during the Cold War given the ongoing crisis. Here are some frequently asked questions and answers about Ukraine and nuclear weapons.

Did Ukraine have nuclear weapons?

When the Soviet Union broke up in 1991, there were thousands of former Soviet nuclear warheads, as well as hundreds of intercontinental ballistic missiles and bombers, left on Ukraine’s territory, which it decided to transfer to Russia. Ukraine never had an independent nuclear weapons arsenal, or control over these weapons, but agreed to remove former Soviet weapons stationed on its territory.

When did Ukraine transfer these nuclear weapons?

In 1992, Ukraine, alongside Belarus and Kazakhstan which also had former Soviet nuclear weapons on its territory, signed the Lisbon Protocol, agreeing to accede to the Nuclear Non-Proliferation Treaty as non-nuclear weapon states as soon as possible. Ukraine subsequently joined the Nuclear Non-Proliferation Treaty as a non-nuclear weapon state in 1994. The transfer of all nuclear material took some time, but by 2001, all nuclear weapons had been transferred to Russia to be dismantled and all launch silos decommissioned.

What is the Budapest Memorandum?

In 1994, Russia, the United Kingdom and the United States signed the Budapest Memorandum, recommitting to obligations under the UN Charter to respect Ukraine’s sovereignty and to not use force against its territorial integrity or independence and re-stating their policy of not using nuclear weapons against non-nuclear-armed states, unless that state attacked them in partnership with a nuclear-armed state. The use of force or invasion of Ukraine would be in violation of this Memorandum, but first and foremost, of the UN Charter, on which the Memorandum is based.

Would Russia have invaded Ukraine if it still had Soviet nuclear weapons stationed on its territory?

There is little convincing historical evidence that the possession or presence of nuclear weapons definitively prevents conflict, when many other variables may be considered, including the prohibition of the use of force under the UN Charter or even just luck. Even beyond this, it is not clear that Ukraine would have been able to take control of former Soviet nuclear weapons, technically or politically. What we do know is that the possession of nuclear weapons by Russia and the United States clearly has not prevented the threat of conflict between Russia and a U.S. ally or the potential humanitarian consequences of any conflict for civilians in the region.

What does the current conflict have to do with nuclear weapons stationed in Europe?

The stationing of U.S. nuclear weapons in Europe, as well as Russia's own short-range nuclear weapons systems designed for European targets, elevates the risk of nuclear weapon use in any conflict in the region. The stationing of Russian nuclear weapons in other countries would only further heighten tensions and increase the risks of use. Recent concerning developments in this direction, such as Belarus’ referendum to modify its constitution to remove its nuclear-weapon-free goal or Russian Deputy Foreign Minister Ryabakov’s remarks that he could not rule out military deployments to Cuba or Venezuela, should be condemned. Thankfully international agreements, like regional nuclear weapon free zones and the Treaty on the Prohibition of Nuclear Weapons, would prohibit many countries around the world, including Cuba and Venezuela, from stationing nuclear weapons on their territory. It is more important than ever that countries hosting U.S. nuclear weapons join the TPNW and remove these weapons to reduce the risk of nuclear weapon use in Europe.