Facing intense diplomatic pressure, the Croat army abruptly halted its advance into Bosnia. Croatian President Franjo Tudjman sent the order after a blunt, televised warning by U.S. Deputy Secretary of State Strobe Talbott: "The light here is red. It's a red stop light. Stop the fighting. Go back to the negotiating table." While Bosnian government troops have advanced to within 25 miles of Banja Luka, Croat forces had crossed the border and now threaten the Serb stronghold from the north. "U.N. military analysts say the Croats and Muslims aren't strong enough to take Banja Luka -- the city's too well defended," Alexandra Stiglmayer reports from Sarajevo. "But they could certainly get within artillery range and lay seige to the city." Assistant Secretary of State Richard Holbrooke will meet with Tudjman and Bosnian President Alija Izetbegovic in Zagreb today to try to rein in the combined Muslim-Croat forces, whose recent advances could threaten peace talks.