President Ronald Reagan’s longtime secretary of state, George P. Shultz, who spent most of the 1980s trying to improve relations with the Soviet Union and forging a course for peace in the Middle East, has died. He was 100.

Shultz died on Saturday at his home on the campus of Stanford University, according to the Hoover Institution, a think tank where he was a distinguished fellow.

Shultz held three major cabinet posts in Republican administrations during a long career of public service. He was labour secretary and treasury secretary under President Richard Nixon before spending more than six years as Reagan’s secretary of state.

Shultz negotiated the first-ever treaty to reduce the size of the Soviet Union’s ground-based nuclear arsenals.