The invitation, carried by the state-run Tanjug news agency has come only days before secretary general Kofi Annan is scheduled to submit a report in compliance with a UN Security Council resolution, essentially demanding an end to the Kosovo offensive by Serbian police and the Yugoslav army. It threatens unspecified further action if the demand is ignored, a condition seen by some NATO countries as opening the door to military intervention.

Ethnic Albanian leader Ibrahim Rugova said here today NATO military strikes in Kosovo would be a humanitarian move that would save the Serbian province's majority Albanian population. He spoke on the heels of a series of reported massacres of Albanian villagers.

``The most critical issue is to stop the war machine of Belgrade and to protect the peopleof Kosovo,'' Rugova told reporters, when asked about the effectiveness of any eventual air strikes. ``That's an issue of humanity. Otherwise we will be seeing other massacres as we've already seen in the past few weeks.''

The 15-member Security Council meanwhile assailed those responsible for butchering ethnic Albanian civilians in the southern Serb province while postponing until next week discussion on military action aimed at halting Serbian assaults.

``Council members strongly condemn those responsible for these atrocities, and called on President (Slobodan) Milosevic and the government of Belgrade immediately to investigate, and identify and punish those responsible,'' said Council President Sir Jeremy Greenstock.

The massacre of an ethnic Albanian family of 18 at the weekend in central Kosovo forest triggered widespread condemnation after eye-witness accounts were published, and prompted Britain to call the Council into emergency session.

While the Council did not assign blame for theatrocities, Annan repeated on Thursday: ``I utterly condemn the unwanted killings and the excesses by Serb security forces, and I think that violence by all sides must stop immediately.''

No decision on military action is expected until Annan delivers his report to the Council. A negative report from Annan is widely seen as a likely trigger for a NATO attack.

Annan's report is expected on Monday, earlier than originally scheduled, because of pressure from Britain and the United States.

The United States and Britain, among others, have issued stern statements warning Milosevic that his forces face airstrikes unless they are withdrawn and he begins meaningful talks with Albanians in Kosovo.

British Prime Minister Tony Blair said on Thursday it was clear ``a diplomatic solution alone'' could no longer deal with the situation in Kosovo.

In Bonn, German Foreign Minister Klaus Kinkel warned Belgrade that the international community's patience ``is exhausted''.

Moving one step closer to the strikes, NATOpermanent representatives on Thursday issued an ``activation request'', which gives allies about 48 hours to designate their forces.

The plan calls for escalating air strikes against Serb military targets, beginning with a limited cruise missile strike and followed by more intense and widespread bombardments if Milosevic does not back down.

In Belgrade, Serbian Deputy Prime Minister Vojislav Seselj threatened the West on Thursday with retaliation against any NATO air raids on targets in Serbia.