International Nuclear Safety Group the Kyshtym disaster, which occurred at Mayak, a Nuclear fuel reprocessing plant in the Soviet Union. Since then, there have been hundreds of nuclear accidents, some considered minor while others were horrendous, with one of the worst accidents being the Chernobyl disaster of April 26, 1986. Involving a nuclear power plant at Chernobyl, now in Ukraine, a combination of nuclear volatility and the disregard of several safety procedures caused an explosion of its fourth reactor, ending in the worldwide environmental and human catastrophe. Following the Chernobyl accident, the IAEA was forced to create a new branch of their organisation to
Nuclear weapons and Ukraine of Independent States. In 1994 Ukraine agreed to destroy the weapons, and to join the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). As a republic in the Soviet Union, Ukraine was the base for the following nuclear forces: International relations theorist John Mearsheimer predicted a Ukraine without any nuclear deterrent was likely to be subjected to aggression by Russia, but this was very much a minority view at the time. A 2016 study argues that the denuclearization of Ukraine was not a "stupid mistake" and that it is unclear that Ukraine would be better off as a nuclear state.