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US President Bill Clinton, Russian President Boris, Yeltsin, and Ukrainian President Leonid Kravchuk sign the Trilateral Agreement on transferring nuclear weapons from Ukraine to Russia and associated matters in Moscow, January 1994. Photo credit: Joseph P. Harahan, historian of the Defense Threat Reduction Agency, and the Clinton Presidential Library.

Why security assurances are losing their clout as a nuclear nonproliferation instrument

By Ariel E. Levite | Nuclear Weapons

Russia launches invasion of Ukraine - Putin's troops 'seize control' of Chernobyl nuclear disaster site. Source: Sky News. https://news.sky.com/story/russia-launches-invasion-of-ukraine-forces-trying-to-seize-site-of-chernobyl-nuclear-disaster-12550026

Russia’s invasion of Ukraine invalidates key international relations assumptions

By François Diaz-Maurin | Nuclear Risk, Nuclear Weapons, Opinion

Watch the 2025 Doomsday Clock announcement on January 28