George Shultz, Ronald Reagan's genial secretary of state who identified a diplomatic opening that helped end the Cold War but contributed to a new brand of conflict by advocating preemptive strikes, has died. He was 100.

"One of the most consequential policymakers of all time, having served three American presidents, George P Shultz died Feb 6 at age 100," the Hoover Institution think tank said in a statement published on its website.