A Fresh Warning To The Serbs

William Cohen came close to giving Serb President Slobodan Milosevic an ultimatum Friday, reports CBS News National Security Correspondent David Martin.

The U.S. Secretary of Defense warned that the crisis in Kosovo "has to be resolved certainly within a week."

That deadline is driven by the approach of winter and the danger it poses to the estimated 50,000 refugees who are living in the hills of Kosovo. They are afraid to return home because of the continuing presence of Serb army and police units in the separatist province.

However, while winter keeps closing in, the timetable for NATO military action keeps slipping. NATO is currently not expected to authorize air strikes until Monday.

U.S. officials believe that authorization of strikes will give special envoy Richard Holbrooke the clout he needs to convince Milosevic he has no choice but to accede to NATO demands.

Holbrooke was still engaged in protracted talks with Milosevic Friday night in a last-ditch effort to stop the Kosovo crisis from turning into a shooting war.

Holbrooke was trying to persuade Milosevic to avert threatened NATO air strikes by obeying a six-point ultimatum from the Big Power Contact Group comprising the United States, its European allies and Russia.

Holbooke had no comment about the talks, which State Department spoeksman James Foley described as "tough."

Foley said the situation in Kosovo appeared to be quiet, but there was no sign that more Yugoslav troops and police were meeting the U.N. demand that they end a bloody crackdown on pro-independence ethnic Albanians there.

On Friday, what may be the last humanitarian aid to reach one of the worst-hit areas of Kosovo made its way to a distribution point, reports CBS News Correspondent Allen Pizzey.

American-donated food, wheat, blankets and foam mattresses reached ethnic Albanians who are desperately in need because their homes have been burned and bombed.

Free access for relief agencies is one of the conditions the Serbs must meet to avoid air strikes.

However, the relief effort for Kosovo has all but ground to a halt in anticipation of NATO bombing raids -- aid agencies have withdrawn most of their foreign staff out of concern for their own safety.

Only a handful of Western aid workers are left in Kosovo, and those who have been forced to evacuate are bitter.

"The U.S. and NATO aren't telling us what's going on," said one, and worst of all there appears to be a total lack of concern about what happens in the ground after air strikes.

Guerrillas of the Kosovo Liberation Army (KLA) fighting for independence were observing the first day of a unilateral cease-fire Friday. However, as one relief worker put it, unless some force comes in to take control on the ground when the bombing stops, the KLA and the Serbs will geback to business as usual.

From a humanitarian point of view, it's the worst case scenario imaginable.

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