The NPT is the primary international framework limiting the spread of nuclear weapons, signed by 191 states and extended indefinitely in 1995.
Key Facts
- Opened for signature
- 1968-07-01
- Entered into force
- 1970
- State parties (as of Aug 2016)
- 191 states
- Combined nuclear warheads (5 states)
- 13,400 warheads
- Extended indefinitely
- May 1995
- Non-member nuclear states
- India, Israel, Pakistan
By the Numbers
Location
Cause → Event → Consequence
By the mid-1960s, fears of rapid nuclear proliferation were acute, with predictions of 25 to 30 nuclear-armed states within two decades. The United States, Soviet Union, and others sought a multilateral mechanism to halt the spread of nuclear weapons technology beyond the five states that had already tested devices.
Negotiated between 1965 and 1968 by the UN-sponsored Eighteen Nation Committee on Disarmament in Geneva, the NPT was opened for signature on 1 July 1968. It established legally binding obligations to prevent proliferation, promote peaceful nuclear cooperation, and pursue disarmament, defining five recognized nuclear-weapon states: the US, Russia, the UK, France, and China.
The treaty entered into force in 1970 and was extended indefinitely in 1995, becoming the cornerstone of global non-proliferation efforts with 191 state parties. It was followed by the 1996 Comprehensive Nuclear-Test-Ban Treaty and the 2017 Treaty on the Prohibition of Nuclear Weapons, though critics note persistent disarmament shortfalls and cases such as North Korea's withdrawal in 2003.
Political Outcome
Treaty entered into force in 1970; extended indefinitely in 1995; 191 state parties as of 2016
Unregulated potential for widespread nuclear weapons acquisition among many states
Internationally codified non-proliferation regime with 191 signatories and IAEA verification