Under U.S. Pressure, Bosnian Serb Commander Announces Cease-Fire : Balkans: While truce is heralded as breakthrough, relief officials express dismay at its cost.

With President Clinton in Washington vowing a diplomatic “full-court press” against Serbia and its allies in Bosnia-Herzegovina, the Serb rebel commander in that shattered republic announced a cease-fire.

But the cease-fire, in a conflict in which dozens of such pacts have proved short-lived, was achieved at a price: The U.N. general waging a dramatic defense of besieged Muslims in eastern Bosnia agreed to Serbs’ demands that he abandon them.

The truce announced by Bosnian Serb Gen. Ratko Mladic and the two top officers of the U.N. Protection Force in the former Yugoslav federation is to take effect at noon Sunday--if Bosnia’s Muslim-led government and Croatian community also endorse it.

A conference of military leaders of all the warring factions was called for April 6 at the Sarajevo airport to work out a permanent solution to the crisis, Mladic said, suggesting that any resolution would have to recognize Serbian territorial conquests.

“Maybe it can be the turning of the tide in this part of the world,” U.N. force commander Gen. Lars-Erik Wahlgren said of the agreements.

While the cease-fire and peace conference were heralded as a breakthrough by Wahlgren and the U.N. chief in Bosnia, French Gen. Philippe Morillon, relief officials expressed dismay at the terms under which the U.N. officers had achieved them.

Morillon had vowed to stay with the hungry and embattled Muslim population in the eastern Bosnian town of Srebrenica until the Bosnian Serb offensive closing in on their desperate enclave ended and humanitarian aid was allowed through.

More than 60,000 Muslim Slavs--nearly half of them refugees from other areas--are trapped in Srebrenica without food or adequate medical attention. Thousands are living in the open with untreated wounds from the incessant Serbian shelling.

Mladic told reporters after the talks with U.N. officers and representatives of the Office of the U.N. High Commissioner for Refugees that Morillon had agreed to leave Srebrenica before the truce takes effect and to take other U.N. military personnel with him.

Morillon later contended the United Nations would “maintain a presence” in Srebrenica but confirmed that he would be leaving.

Muslim civilians wanting to flee Srebrenica will be allowed to leave with Morillon, Mladic added.

Mladic said Serbs demanded that Morillon leave the area because they feared that he might be “assassinated” if he stays beyond Sunday morning. He said that Morillon further agreed to travel through the dangerous siege lines around Srebrenica in a passenger car, without military escort and accompanied by no more than five aides and support staff.

The French general was to travel along with a 20-truck aid convoy to Srebrenica early today, then use the emptied trucks to relocate any Muslims wanting to go to the city of Tuzla, 45 miles to the northwest, which remains under the Bosnian government’s control.

“He’s crumbled,” an outraged aid official declared upon hearing of the conditions under which Morillon won Bosnian Serb agreement on the cease-fire.

The U.N. refugee agency’s special envoy to the republics of the former Yugoslav federation, Jose Maria Mendiluce, conceded grave doubts about the latest cease-fire agreement, which would expose Srebrenica and other targets to easy conquest if Serbs fail to hold their fire.

“I am not so optimistic as the general,” Mendiluce said, referring to Morillon.

Mendiluce questioned why the cease-fire did not come into effect right away and also cast doubt on the logic of setting a peace conference for 11 days hence, in view of U.N. warnings that Srebrenica and the Muslim village of Zepa are on the verge of falling to the Serbs.

While the generals were talking in Belgrade, Serbian gunmen continued to pound both enclaves with heavy artillery, Radio Sarajevo reported.

Mladic said all of the agreements were contingent on support by Bosnian Muslims and Croats.

Morillon said he had verbal assurances from the other two factions that they would support the cease-fire, but the fate of the conference remained unclear.

Wahlgren had announced that humanitarian aid would be resuming throughout Bosnia as a consequence of the accords, but Mladic later disputed that, saying only the goods Morillon was accompanying would be let in.

In Washington meanwhile, Clinton said he would “do everything we can now to put on a full-court press, first diplomatically, to secure the agreement of the Serbs” to a Western-mediated peace agreement already endorsed by the Sarajevo government and Bosnia’s Croatian leader, Mate Boban.

Bosnian Serb leader Radovan Karadzic has refused to sign the plan because it would require Serbs to give back nearly half of the 70% of Bosnia they have conquered. Mladic repeated his side’s opposition to the Vance-Owen formula, saying “it simply has disregarded some realities in Bosnia-Herzegovina.”

The plan, by mediators Cyrus R. Vance and Lord Owen, would carve up the Bosnian republic into 10 ethnic provinces.

Talking to reporters after he and German Chancellor Helmut Kohl had met briefly with Bosnian President Alija Izetbegovic, Clinton said the United States and much of the rest of the world community are out of patience with the Serbs’ bloody campaign of “ethnic cleansing.”

He said the United States is conferring with other U.N. Security Council members about imposing tougher economic sanctions on Serbia, military enforcement of a ban on warplane flights over Bosnia and an end to the arms embargo against the Bosnian government.

If the Serbian faction does not accept the peace plan soon, he said, the council would quickly adopt the new measures; the climate for their approval was far better following the Muslim and Croatian approval of the peace plan.

State Department officials agreed that approval was likely next week of a resolution authorizing allied warplanes to shoot down Serbian military aircraft violating the Bosnia “no-fly zone.” But they said Washington faces an uphill battle to lift the arms embargo imposed on all the republics of the former Yugoslav federation just for the Bosnian government. Some Security Council members fear that such a move would increase the killing.

The number of dead from the past year of war in Bosnia is said to be well over 100,000, and the sieges that began last April 6 and the Serb policy of “ethnic cleansing” have driven nearly half the republic’s 4.4 million people from their homes.

The United States announced Friday that it had agreed to admit up to 3,000 Bosnian refugees, expanding an earlier program that was open only to internment camp prisoners and their families.

Under the new program, Bosnian victims of torture, rape and other atrocities will be permitted to apply, along with members of the families of U.S. citizens and legal residents. So far, only 136 Bosnians have been resettled in the United States, far below the previous quota of 1,000.

Williams reported from Belgrade and Kempster from Washington.