President Clinton announced new sanctions against Haiti's military rulers today, and Americans were encouraged by the State Department to leave the Caribbean nation. Both steps heightened tensions and led to conjectures that a U.S. invasion may be in the works. Other warning signs of a confrontation proliferate, says TIME correspondent Edward Barnes. The French government is evacuating its dependents. The U.S. Marines have begun military exercises off Cuba's Guantanamo, about 100 miles from Haiti's coast. ABC News reports that U.N. documents quote Deputy Secretary of State Strobe Talbott as saying the U.S. will not wait beyond the end of July before using force. In Haiti the government has responded with attacks by thugs on U.N. observer teams, beating up several officials.