Relations between the U.S. and the Soviet Union (later Russia) within the UN have evolved in step with the larger geopolitical situation between the two powers. While the Soviet Union was boycotting the Security Council and China's seat was represented by U.S.-friendly Republic of China (instead of the communist People's Republic of China which would replace the ROC in the UN in 1971), the U.S. and UN jointly condemned the invasion of South Korea by North Korean troops, leading to the UN sanctioned Korean War. Later, the U.S. persuaded all permanent members of the Security Council to authorize force against Iraq after it invaded Kuwait in 1991. This was a major step toward U.S. and Russian reconciliation after the end of the Cold War.