After eight hours of negotiations, the Atlantic alliance on Saturday gave Secretary General Javier Solana the authority to order military action if the six-nation Contact Group deems it necessary.

The BBC's Orla Guerin reports from Kosovo on "another day of burying the dead"

Nato's decision reinforces the warning delivered in person to both sides by UK Foreign Secretary Robin Cook that they must come to peace talks in France and that they must reach a deal to end the Kosovo conflict within three weeks - or risk military action.

Dr Solana's authorisation means he can call air strikes on Serbian targets after a final telephone "consultation" with the six countries of the Contact Group, effectively shortening the decision-making process.

Javier Solana: "Nato is ready"

"Nato stands ready to act," Dr Solana told reporters at Nato's Permanent Council in Brussels.

Nato's message was backed by Britain and the United States. In a joint statement, UK Prime Minister Tony Blair and visiting US Vice President Al Gore warned that both countries were prepared to use force to prevent further humanitarian disasters.

Nato can call in air strikes after talks with Contact Group

Mr Blair said: "What is absolutely clear to both sides now is that we are serious about putting in place a political agreement and we have the necessary preparations to use force to back that up. The fact that we now have a deadline, an ultimatum, is a huge step forward."

Nato has 200 aircraft on stand-by in Italy and on aircraft carriers in the Adriatic Sea, should the Contact Group and the Atlantic alliance give the go-ahead for air strikes.

No-one said 'no'

On his flying visit to Yugoslavia on Saturday as chairman of the Contact Group, Mr Cook did not receive immediate positive responses from all sides.

Yugoslav President Slobodan Milosevic promised to give the six-nation group an answer within the next few days, but demonstrated some resistance to the idea of international peace talks by saying negotiations to end the Kosovo conflict should take place in Serbia.

However, Ibrahim Rugova, the moderate "president" of the ethnic Albanian majority in Kosovo and influential publisher Veton Surroj told Mr Cook they would attend talks.

But Western diplomats have described Mr Rugova as increasingly irrelevant, while the key players in Kosovo are now the rebels of the KLA. Their representative, Adem Demaci, has, like the Serbs, decided to take several days to consider his answer.

Western diplomats said it was encouraging that no side had given an outright "no", but they have underlined that the participation of key players should not be taken for granted.

The BBC's Stephen Gibbs: "Three weeks to solve a conflict that has simmered for centuries"

Mr Cook said no one group would be allowed to veto the peace talks, but the BBC Correspondent in Pristina, Jacky Rowland, said the rebels effectively had the power of veto because negotiations without them would be meaningless. Up until now, the KLA has rejected any solution short of independence.

The Contact Group's proposals, which would form the basis of any peace talks in France, suggest "substantial autonomy" for Kosovo.

A deal would give Kosovo its own elected assembly, a local security force and an international armed presence to police the peace settlement.

Violence continuing

But all the warring factions still have to agree to come to the peace table, and while the major powers engage in diplomacy, violence is continuing on the ground.