Montenegro's announcement that it wants to break up the unhappy family known as Yugoslavia was greeted in Serbia today with resignation over a separation that already exists in fact, but with umbrage over what many here saw as temerity by the tiny republic seeking to dump its dominant partner.

The proposal to abolish the Yugoslav federation and replace it with a loose "Association of the States of Montenegro and Serbia," put forward Thursday by Montenegro, represented a major embarrassment for Slobodan Milosevic, the Yugoslav and Serbian leader.

Since his office is that of Yugoslav president, Milosevic in theory would be left presiding over a nonexistent country if Serbia's last partner in the federation were to go its own way. Although Milosevic clearly rules in Belgrade, the republic of Serbia has had its own president, Milan Milutinovic, since Milosevic moved to the federal presidency in 1997 to get around a Serbian term limit.

Milosevic made no official comment and the main government-controlled newspapers and television stations largely ignored the proposal from the Montenegrin government. Podgorica, the Montenegrin capital, was quiet today, with people out on the streets as normal, and the 20,000 Yugoslav army troops stationed in Montenegro showed no signs of movement.

But Goran Matic, a Yugoslav minister without portfolio who serves as a government spokesman, denounced the move as American manipulation. He called it the culmination of an intensive effort by the Clinton administration to dissolve Yugoslavia as part of the hostilities lingering from the recent war over Kosovo.

Opposition groups in Serbia expressed acceptance of Montenegro's move but indicated they were miffed by the timing and worried that it could distract from their own efforts to oust Milosevic.

"There is no doubt that a redefinition of relations between Serbia and Montenegro is needed because the current situation is unsustainable," said a spokesman for the Social Democratic Party of retired Gen. Vuk Obradovic. But he said Milosevic should be removed first so the person "most responsible" for the rocky relationship between the two republics would not be making decisions about their future.

"Now even brother Montenegrins don't want to live with us anymore," lamented one Belgrade resident. "Who gives a damn?" retorted another. "If they want to go their own way, let them."

In contrast to favorable U.S. government assessments, Montenegrin President Milo Djukanovic is viewed by many Serbs as a "cynical opportunist," an independent critic of the government here said.

"We do envy Montenegro for having escaped Milosevic's grip," he added. "But this does not mean it's a shining example of democracy and freedom for us."

The Montenegrin proposal calls for separate army commands, separate foreign ministers for the next two years and economic independence, including the right of Montenegro to introduce its own currency. The bicameral federal legislature would be replaced by a unicameral parliament of the association; a "council of ministers" would replace the Yugoslav government. It would consist of a president--effectively occupying the post that Milosevic now holds--and five ministers instead of the present 21.

Under existing law, constitutional changes--and the Montenegrin proposal amounts to junking the entire Yugoslav constitution--require a two-thirds vote in both houses of the legislature. Passage would appear unlikely. But if their proposal is rejected, Montenegrin officials said their next move would be to hold a referendum on independence.

In such a case, analysts here said, Montenegro--an area roughly the size of Maryland with a a population of 630,000--could have more to lose than Serbia, which has a population of more than 10 million. By some estimates, more Montenegrins live in Serbia than in their own republic, and many of Montenegro's inhabitants consider themselves Serbs.

Montenegro depends on Serbia for electricity and food; for Serbia, Montenegro represents mainly a source for smuggled goods and an outlet to the Adriatic Sea. But Montenegro's port of Bar is poorly equipped, and the Danube River, which runs through Belgrade, is considered a more strategic shipping channel.

On the other hand, Montenegro's move would make it even more of a refuge for Serbian opponents of Milosevic, who have found the republic a useful sanctuary from political persecution in Belgrade. Among those who have fled there recently is Zoran Djindjic, one of the leaders of the opposition Alliance for Change.

He said he wished Montenegro would "wait for democratization" in Serbia--meaning the removal of Milosevic--before pressing ahead with its proposal. While he sees no chance that Milosevic would use military action to keep Montenegro in the federation, Serbs within Montenegro could pose a challenge, he said.

"I think the problem can arise in Montenegro itself," Djindjic said, "because there are strong forces there that will be against this."

The Associated Press reported from Kosovska Kamenica, Yugoslavia:

Russian peacekeepers in Kosovo came under attack three times late Thursday and today, revealing widespread animosity among ethnic Albanians toward Moscow's growing presence in the Serbian province.

The Russians were targeted at checkpoints in eastern Kosovo by unidentified assailants in three separate incidents, including a sniper attack at their main base in Kosovska Kamenica, a Russian officer confirmed. Maj. Jenya Zokolov, said one of his soldiers was shot while on patrol in the American sector in eastern Kosovo. He said a U.S. helicopter evacuated the soldier.

The attacks came just one night after about 1,000 ethnic Albanians marched to the Russian base in Kosovska Kamenica in protest. Kosovo Albanians view the 3,600 Russians as pro-Serb, and Russian mercenaries are said to have fought alongside Serbian forces in their campaign of massacres and expulsions against ethnic Albanians that precipitated the NATO air campaign against Yugoslavia in March.

Correspondent Peter Finn in Podgorica, Yugoslavia, contributed to this report.