President Kennedy Ratifies the Limited Nuclear Test Ban Treaty

The Treaty banning Nuclear Weapon Tests In The Atmosphere, In Outer Space And Under Water, often abbreviated as the Partial Test Ban Treaty (PTBT), Limited Test Ban Treaty (LTBT), or Nuclear Test Ban Treaty (NTBT) (although the latter also refers to the Comprehensive Test Ban Treaty) is a treaty prohibiting all test detonations of nuclear weapons except underground. It was developed both to slow the arms race (nuclear testing was, back then, necessary for continued nuclear weapon advancements), and to stop the excessive release of nuclear fallout into the planet's atmosphere.

It was signed by the Governments of the USSR (represented by Andrei Gromyko), the UK (represented by Sir Alec Douglas-Home) and the USA (represented by Dean Rusk), named the "Original Parties", at Moscow on August 5, 1963 and opened for signature by other countries. It was ratified by the U.S. Senate on September 24, 1963 by a vote of 80 to 19. The treaty went into effect on October 10, 1963.

The 1963 Partial Test Ban Treaty (PTBT) prohibits nuclear weapons tests "or any other nuclear explosion" in the atmosphere, in outer space, and under water. While not banning tests underground, the PTBT does prohibit underground nuclear explosions that cause "radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control" the explosions were conducted.

The Treaty was initialed on 25 July and formally signed at Moscow on 5 August 1963. It entered into force on 10 October when the three original signatories (US, UK, USSR) deposited their instruments of ratification.

The Treaty is of unlimited duration. The Treaty has not been signed by France or China.