FILE - In this May 29, 1972, file photo, President Richard M. Nixon shakes hands with Communist Party leader Leonid Brezhnev in Moscow after the two signed a joint statement. Premier Alexei Kosygin is at center. When U.S. and Russian presidents meet, the rest of the world stops to watch. For decades, summits between leaders of the world powers have been heavily anticipated affairs in which every word, handshake and facial expression is scrutinized. (AP Photo/File)