July 7, 2017, UN Headquarters in NYC. 122 countries meeting at the United Nations conference in New York adopted a Treaty on the Prohibition of Nuclear Weapons, the first multilateral legally-binding instrument for nuclear disarmament. The treaty "prohibits a full range of nuclear-weapons-related activities, such as undertaking to develop, test, produce, manufacture, acquire, possess or stockpile nuclear weapons or other nuclear explosive devices, as well as the use or threat of use of these weapons".