1. Limited Test Ban Treaty:
Banned nuclear weapon tests in the atmosphere, in outer space and under water signed by the US, UK and USSR in Moscow on 5 August 1963 came into force on 10 October, 1963.
2. Nuclear Non-Proliferation Treaty:
It allows only the nuclear weapon states to have nuclear weapons and stops others from acquiring them. A nuclear weapon state is one which had manufactured and exploded nuclear explosive device prior to 1 January, 1967. So there are five nuclear weapon states: US, USSR, Britain, France and China.
3. Strategic Arms Limitation Talks I and II (Salt I and II):
The first round began in November 1969. The Soviet Union leader Leonid Brezhnev and the US President Richard Nixon signed the following in Moscow on 26 May 1972—
• Anti Ballistic Missile System Treaty,
• Interim Agreement on limitation of strategic offensive arms. It came into force on 3 October, 1972. The second round started in November 1972.The US President Jimmy Carter and the Soviet leader Brezhnev signed Treaty on limiting strategic offensive arms in Vienna on 18 June, 1979.
4. Strategic Arms Reduction Treaty I and II (START I and II):
Treaty I signed by the USSR President Mikhail Gorbachev and the US President George Bush (Senior) on the reduction and limitation of strategic offensive arms in Moscow on 31 July 1991. Treaty II was signed for the same purpose in Moscow on 3 January, 1993 between Russian President Boris Yeltsin and the US President George Bush (Senior).