Government troops inched forward in central Bosnia on Sunday, chipping away at rebel-held territory while Serbs struggled to hold their ground and cope with a sudden flood of refugees.
Serbs fought back on other fronts, firing artillery that killed three people in the U.N.-declared safe areas of Sarajevo and Tuzla.
In Sochi, Russia, Foreign Minister Andrei Kozyrev said he and U.S. officials narrowed their differences in talks on a new approach to ending four years of war in former Yugoslavia. Both sides are pressing for a meeting between the presidents of Serbia, Croatia and Bosnia.
Offensives by allied Croatian and Muslim-led Bosnian government forces beginning Saturday in southern and western Bosnia appeared intended to keep the Serbs off-balance.