A further 200,000 people are believed to be making their way towards the borders. And the United Nations says it fears there will soon be no ethnic Albanians left in the Serbian province.

In another development, the United States is holding a Yugoslav army officer as a prisoner of war following his capture by the Kosovo Liberation Army.

And Nato's supreme commander for Europe, General Wesley Clark, has warned Mr Milosevic that the allies will destroy him if he does not change his policies.

(Click here for maps showing latest Nato strikes and refugee movements)

Tens of thousands of refugees are pouring into Albania and Macedonia, arriving hungry and exhausted after trekking through heavy storms.

Jeremy Bowen reports: "The refugees are torn from their homes by order of Slobodan Milosevic"

Nato spokesman Jamie Shea accused the Serbs of renewing a "no mercy policy" against Kosovo Albanians, increasing efforts to expel them from the province.

But he added: ''I personally do not believe that Milosevic is going to succeed in throwing everybody out before we stop him.''

Although refugees were safer outside Kosovo, Mr Shea said Nato did not want Albanians to leave the province.

''It is essential for the future of Kosovo that a certain number of people are able to stay there,'' he added. ''Our aim will be to do everything we possibly can to stop the violence before the last Albanian is pushed across the frontier.''

And he insisted the ethnic cleansing would be reversed in the long run with all refugees being returned.

Atrocities

Mr Shea said there was mounting evidence of mass graves in the province - a very rough calculation indicated 3,200 people had been killed in the last few weeks.

Paul Royall reports: "More serious tests for those handling the crisis"

Refugees have reported summary executions in at least 50 towns and two major massacres. Nato said an aerial photograph showed probable mass graves for 150 people at Izbica village.

The BBC has also seen further evidence of alleged slaughter. A videotape handed over by a refugee shows six men said to have been killed by Serbs for refusing to leave their home.

Refugee exodus

Less than a quarter of the province's two million or so Albanians remain in Kosovo, according to the UN refugee agency (UNHCR).

At least 14,000 refugees have entered Albania since Friday morning and witnesses spoke of a 15km (10 mile) column heading to the border.

Thousands continue to pour into Albania

Another 7,800 refugees crossed into Macedonia on Friday and 3,200 into Montenegro. Some said the Serbs had shot at them as they left.

Nato said 100,000 refugees were believed to be bound for Macedonia and a similar number for Albania.

The UNHCR says the situation is terrible and the World Food Programme has reported the first signs of malnutrition among children.

Jonathan Charles reports: "Troops will be put back in if needed"

The exodus continued as Nato launched Operation Allied Harbour to help refugees in Albania. The force, which will number more than 7,000 troops, will fly people from the border to safer areas near the coast.

'Milosevic losing'

On Saturday, General Clark flew to the region for talks with Macedonian and Albanian leaders.

He said Mr Milosevic was losing the conflict against Nato forces which would "destroy everything that (he) values" unless he complied with international demands.

But the Yugoslav Government has rejected a new five-point peace plan put forward by UN Secretary-General, Kofi Annan.

The BBC's Rageh Ommar: The expulsion was methodical

The Yugoslav ambassador to the UN said Serbia would not allow the deployment of an international force in Kosovo and would not withdraw from the province.

Prisoner of war

Meanwhile, Nato is holding its first prisoner of war since the start of its campaign against Yugoslavia. Mr Shea said the soldier had been seen by a doctor and was in good condition.

The Pentagon said KLA fighters captured the Yugoslav soldier earlier this week. He was taken across the border and delivered to the Albanian Government, who handed him over to the US.

Quiet night

Friday night was one of the quietest Yugoslavia has seen since the start of the Nato raids three weeks ago. Military officials blamed bad weather.

Serb media reported raids on in Valjevo and the Uzice region, both south of Belgrade.

Nato said its aircraft had destroyed seven tanks, armoured vehicles and field forces during daytime raids.

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