generate questions: In May 1972, President Richard M. Nixon and Soviet Premier Leonid Brezhnev negotiated an easing of relations known as detente, creating a temporary "thaw" in the Cold War. In the spirit of good sportsmanship, the time seemed right for cooperation rather than competition, and the notion of a continuing "race" began to subside.
Which two world leaders had negotiations that relieved the Cold War? {sep_token} When did President Nixon and Brezhnev of the USSR end the Cold War?