On 31 July 1991, in Moscow, George H. W. Bush and Mikhail Gorbachev sign START I (Strategic Arms Reduction Treaty) — the first agreement substantially cutting US and Soviet strategic nuclear arsenals.

The treaty caps and reduces intercontinental ballistic missiles, submarine-launched missiles and heavy bombers, with a detailed verification regime.

Negotiated at the end of the Cold War, START I enters into force in 1994 (after Russia’s succession) and remains a pillar of arms control until expiry/replacement.

The signing comes months before the USSR’s dissolution, symbolising the shift from the arms race to mutual reductions.

For arms control, 31 July 1991 marks the signing of the first START.

The official text is on the State Department site / treaty collections.

START I of 31 July 1991 remains the milestone of US–USSR/Russia strategic arsenal reduction.

Image: Moscow / strategic arms; Wikimedia Commons. Cropped to 16:9.

Source consulted: START I. Treaty text: START I (US State Department).