The five permanent members of the United Nations Security Council, China, France, Russia, the United Kingdom, and the United States, are five nuclear-weapon states that have signed the Nonproliferation Treaty (NPT). As the P5, they meet regularly to work toward nuclear disarmament and nonproliferation.
First conference, September 3 to 4, 2009, in London.
Second conference, June 30 to July 1, 2011, in Paris.
Third conference, June 27 to 29, 2012, in Washington, D.C.
Fouth Conference, April 18 to 19, 2013, in Geneva.