Key Serb Meeting Exposes Deep Rifts : Balkans: President Milosevic suffers major setback with disastrous bid to form pan-Serbian parliament. Name-calling, walkouts mar conference.

BELGRADE, Yugoslavia — Serbian President Slobodan Milosevic on Friday suffered one of the most damaging setbacks of his six years in power when a gathering he called to rally Serbian leaders behind a Western peace plan collapsed into a melee of name-calling and protests.

The fractious pan-Serbian conference organized by Milosevic exposed deep rifts among the region’s Serbs, whose quest for unity through the forcible building of a Greater Serbia has ripped apart the former Yugoslavia and sparked ethnic fighting that has left more than 150,000 missing or dead.

Milosevic had summoned elected and self-styled Serbian lawmakers from throughout the war-torn Balkans to marshal support for a peace plan repeatedly rejected by Bosnian Serbs.

While the session did produce a largely meaningless endorsement of the proposed settlement, that vote came only after bitter verbal clashes between rivals and supporters of Milosevic that prompted dozens of the deputies to storm out.

Milosevic has skillfully recovered from several earlier incidents that threatened his grip on power, but observers of the disastrous first attempt at creating a pan-Serbian parliament said it probably marked the beginning of the end of his rule.

“His weakness has been exposed,” one Belgrade-based diplomat observed of Milosevic. “He can no longer manipulate the elected institutions to do his bidding.”

Although none of those who spoke at the raucous parliamentary session criticized Milosevic by name, they derailed his attempt to isolate and intimidate those Serbian leaders who dare defy Belgrade.

Bosnian Serbs are holding a popular vote this weekend on the peace proposal of U.N. mediator Cyrus R. Vance and his European Community partner, Lord Owen. The plan has already been rejected three times by the Bosnian Serbs’ self-proclaimed parliament and is widely expected to be voted down again in the referendum.

It would carve up Bosnia into 10 ethnic provinces and give rebel Serbs control of more than half of the land they have conquered, but at the price of renouncing their long-held dream of uniting with all Balkan Serbs in a Greater Serbia.

Milosevic was the key figure in arming and instigating Serbian rebellions in Croatia and Bosnia, but he has lately sought an end to the bloodshed in hopes of getting harsh U.N. sanctions lifted from his own country.

Friday’s gathering was called in an attempt to scuttle the weekend referendum, but Bosnian Serb leader Radovan Karadzic and other rebel lawmakers refused to cancel the vote or attend the Belgrade meeting.

That snub added to the insult dealt Milosevic a week earlier when the Bosnian Serb parliament ignored his personal appeal to support the Vance-Owen peace plan.

Rather than providing a forum for ganging up on the absent Bosnians, the pan-Serbian session was taken up with procedural squabbles that deteriorated into political mudslinging and criticism of the effort to abandon the Bosnian Serbs.

Serbian Radical Party leader Vojislav Seselj, one of several Belgrade paramilitary commanders identified by the U.S. government as a war crimes suspect, argued that no decision of the gathering would carry any significance without the participation of Bosnian Serbs, who sent only a team of observers.

Goran Hadzic, a Milosevic ally posted to govern the Krajina region seized from Croatia during the 1991 Serb-Croat war, spoke of the need for peace and Serbian unity, only to be lambasted by other Croatian Serbs as a “Bolshevik” and by Seselj as a Belgrade toady “who doesn’t even know how his people live.”

After Milosevic sycophants and rivals traded accusations for two hours, Seselj led a theatrical walkout of nearly half the 370 Serbs in attendance to protest what he called an illegitimate meeting.

“Milosevic thinks he can do something on his own personal authority,” Montenegran deputy Novak Kilibarda complained after following Seselj out of the conference hall. “He’s not a traitor, but he’s a bad politician.”

Those left after the walkout eventually voted unanimously to endorse the Vance-Owen peace plan, although the significance of their action was unclear.

“We support the peace plan for Bosnia as the only solution offered by the international community for cessation of hostilities,” read the declaration approved by Milosevic and his allies.

Bosnian Serb leaders in their rebel headquarters in the town of Pale, near Sarajevo, immediately denounced the Belgrade decision as invalid.

“This parliament has not contributed anything important to the whole situation, especially since a large group of deputies walked out,” Momcilo Krajisnik, chairman of the rebel parliament, told the British news agency Reuters.

The Bosnian Serbs’ military commander, Gen. Ratko Mladic, also signaled continued intransigence by threatening to cut off food and supplies to U.N. peacekeeping troops protecting Muslim civilians in Serb-besieged areas. Mladic contends that U.N. officials have reneged on the terms of a cease-fire for the embattled eastern Bosnian town of Srebrenica.

The fiery general who has led the rebels’ resistance to the Vance-Owen peace plan also was accused by U.N. sources Friday of having ordered an attack on the Muslim-held town of Brcko.

Sporadic fighting was also reported Friday from the southern Bosnian city of Mostar, where Spanish U.N. troops came under repeated fire as they attempted to approach the line of confrontation between Muslims and Croats.

Mladic and other hard-liners in the Bosnian Serb leadership oppose the Vance-Owen settlement because it would prohibit formal union of the republic of Serbia and territories conquered by Serbs in Bosnia and Croatia.