BELGRADE, Yugoslavia (AP) _ Ethnic Albanian rebels fighting for independence for the Serbian province of Kosovo declared a unilateral cease-fire today.

A statement distributed by the Kosovo Liberation Army from Kosovo's capital of Pristina said the rebel command ``has decided to refrain from all military activity'' starting Friday.

Yugoslav President Slobodan Milosevic launched his crackdown Feb. 28 after attacks by KLA rebels against police and soldiers in the majority Albanian province. He has insisted he needs to maintain a military and police presence in the area to guard against further KLA attacks.

The KLA said in its statement that rebels retain the right to defend themselves if attacked and demand international monitoring of the cease-fire.

The KLA statement puts additional pressure on Milosevic, whose troops have been fighting the secessionists in battles that have left hundreds of people killed and about 270,000 homeless.

Kosovo is in southern Serbia, the main republic in Yugoslavia. About 90 percent of Kosovo's 2 million inhabitants are ethnic Albanians, and most favor independence.

In Brussels, Belgium, NATO officials applauded the KLA cease-fire.

``Any attack ... against Yugoslav forces, makes our job more difficult,'' said one NATO official on condition of anonymity. ``We welcome it.''

The KLA said it declared the cease-fire ``to respect the engagement of the international community to end the civilian tragedy in Kosovo and to fulfill the demands from the U.N. resolution of September 24.''

Meanwhile in Belgrade today, convoys of U.S. and other foreign embassy staff rolled out of the Yugoslav capital while support within NATO for airstrikes to force Milosevic to end his crackdown on separatists in Kosovo appeared to hit a snag.

Tensions between Yugoslavia and NATO nations were intensifying following three days of meetings between Milosevic and special U.S. envoy Richard Holbrooke.

The diplomat briefed Secretary of State Madeleine Albright and NATO officials today in Brussels on the results of those talks and was told by Albright to return to Belgrade for another session with Milosevic.

Albright said Holbrooke would be delivering a message that the time for a diplomatic settlement in Kosovo was ``all but gone.'' She demanded full compliance with U.N. orders to end the crackdown and said ``half measures'' would not be enough.

In Kosovo, reporters heard three or four bursts of mortar fire today in the Malisevo area about 30 miles southwest of the provincial capital Pristina. The firing indicated some military action was continuing, although U.S. officials have conceded there has been no significant fighting for about a week.

Holbrooke was ordered to return amid further signs of opposition within NATO to an attack without further diplomatic efforts.

At the White House today, President Clinton said the United States would vote to authorize military strikes against Serbia if Milosevic ``continues to defy the international community.''

``In the days ahead my counterparts in Europe will be making similar decisions,'' the president said in a ceremony in the Roosevelt Room.

Holbrooke refused to talk to reporters after his final session with Milosevic on Wednesday. But Yugoslavia's Tanjug news agency said Milosevic warned him that threats of NATO airstrikes only dimmed the chances for peace in Kosovo.

Russia's foreign minister, Igor Ivanov, met Milosevic today en route to London for a meeting of the major powers most deeply involved in the negotiations. Russia strongly opposes using force to resolve the crisis, and Ivanov is expected to deliver that message when he meets Albright in London.

In the Yugoslav capital of Belgrade today, about 20 vehicles carrying diplomats and their families from the United States, Britain and Australia left for the Hungarian capital of Budapest. The diplomats will remain in Budapest until it becomes clearer whether NATO will strike to force Milosevic to end his crackdown.

Despite mounting evidence that Milosevic has not complied with U.N. Security Council demands for a cease-fire, the withdrawal of Serb troops, and the return of refugees to their villages, Washington lacks the international consensus needed to bomb Milosevic into action.

Milosevic says he has fulfilled those demands and his office issued a statement Wednesday saying that ``threats, which are delivered to our country, jeopardize the continuation of the political process.''

Holbrooke did succeed in negotiating safe passage for Selman Morina, the sole survivor of a massacre last week in which 13 other ethnic Albanian males were allegedly shot and killed by Serb police. The police deny involvement.

Morina, who was wounded in the leg, left the country Wednesday with 10 family members and will be interviewed by U.N. war crimes investigators in The Hague, Netherlands, said a senior U.S. official speaking on condition of anonymity.

Serbia, meanwhile, announced measures Wednesday that brought the country nearer to war footing. It ordered government departments to increase security and threatened punishment for those who spread ``fear, panic and defeatism.''

Detailed maps showing locations of 46 main Belgrade underground shelters were published in newspapers, including instructions on ``what to do in case of an attack.''