Explanation:

 A nuclear-weapons-free zone (NWFZ) is defined by the United Nations as an agreement which a group of states has freely established by treaty or convention, that bans the use, development, or deployment of nuclear weapons in a given area, that has mechanisms of verification and control to enforce its obligations, and that is recognized as such by the General Assembly of the United Nations. NWFZs have a similar purpose to, but are distinct from, the Nuclear Non-Proliferation Treaty to which most countries including five nuclear weapons states are party. Another term, nuclear-free zone, often means an area which has banned both nuclear power and nuclear weapons, and sometimes nuclear waste and nuclear propulsion, and usually does not mean a UN-acknowledged international treaty.