At least nine nations are believed to have nuclear weapons – the United States, Russia, England, France, China, Pakistan, India, North Korea and Israel. Other nations may have nuclear weapons or are working towards them, most notably Iran. At the height of the Cold War in 1985, there were believed to be 65,000 nuclear weapons in the world. As a result of the Non-Proliferation Treaty and unilateral decisions by some countries, this number has been reduced to about 20,000.