The UN imposed a worldwide oil, arms, and financial embargo on Haiti June 23, 1993. The embargo was suspended when the military agreed to Aristide's return to power on Oct. 30, but the military effectively blocked his return. After renewed sanctions, the UN Security Council authorized, July 31, 1994, an invasion of Haiti by a multinational force. With U.S. troops already en route, an invasion was averted, Sept. 18, by a new agreement for military leaders to step down and Aristide to resume office. As part of the agreement, thousands of U.S. troops began arriving in Haiti, Sept. 19. Aristide returned to Haiti and was restored in office Oct. 15. A UN peacekeeping force exercised responsibility in Haiti from Mar. 31, 1995 to Nov. 30, 1997.