Weapon of mass destruction
The only country to have used a nuclear weapon in war is the United States, which dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki during World War II. There are eight countries that have declared they possess nuclear weapons and are known to have tested a nuclear weapon, only five of which are members of the NPT. The eight are China, France, India, North Korea, Pakistan, Russia, the United Kingdom, and the United States.
United Kingdom and weapons of mass destruction
The United Kingdom possesses, or has possessed, a variety of weapons of mass destruction, including nuclear, biological, and chemical weapons. The United Kingdom is one of the five official nuclear weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons and has an independent nuclear deterrent. The UK has been estimated to have a stockpile of 120 active nuclear warheads and 215 nuclear warheads in total. It had renounced the use of chemical and biological weapons in 1956 and subsequently destroyed its general stocks.