United Nations Under-Secretary-General and High Representative for Disarmament Affairs Izumi Nakamitsu attends the third session of the Preparatory Committee for the 2020 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), at the UN headquarters in New York, April 29, 2019. Izumi Nakamitsu warned on Monday that restraints on nuclear arsenals are weakening. (Xinhua/Li Muzi)