As NATO continued to prepare for action, President Bill Clinton said in Washington that Milosevic had ``made a series of commitments which, if implemented, could achieve the international community's goals in Kosovo''.

US envoy Richard Holbrooke earlier told the NATO allies in Brussels that he had made limited progress in intensive last ditch-talks with Milosevic in Belgrade.

Holbrooke returned to Belgrade early Tuesday for further talks after a brief trip to Brussels. Asked what was left to negotiate, Holbrooke replied: ``I'll rather keep that for tomorrow.'' But he said the talks had ``created some promising possibilities''.

Asked about the effects of the NATO ``activation order'' approved early on Tuesday, Holbrooke said: ``I think that speaks for itself. I don't want to speculate.''

NATO allies unanimously voted an ``activationorder'', a green light for NATO airstrikes on Serb forces in Kosovo fighting Albanian separatists.

But they stipulated that the strike order could not be activated for 96 hours -- Saturday morning -- at the earliest.

``The 96-hour delay,'' NATO secretary general Javier Solana told an early morning press conference at NATO headquarters, ``begins right now.''

Clinton said Milosevic had ``agreed to fully comply with UN Security Council resolution 1199, and accepted an inclusive international inspection and a time table for autonomy arrangements'' for Kosovo and its majority ethnic Albanian population.

``If met,'' he said, ``the commitment can provide the basis for peace and progress.'' ``But commitments are not compliance,'' Clinton added, ``and the Balkan graveyards are filled with President Milosevic's broken promises.''

The allied action appeared to give Holbrooke the leverage he wanted as he headed back to Belgrade for yet another round of talks with Milosevic.

``Progress has been made,'' Solanasaid after hearing from Holbrooke. But he added, ``After a thorough review of the situation in Kosovo, we see that the Yugoslav government still has not complied fully with UN Security Council resolution 1199 in a way that can be verified.''

``I still believe diplomacy can succeed and the use of military force can be avoided,'' Solana said. ``But the responsibility lies on the shoulders of Milosevic. He knows what he has to do.''

Holbrooke, speaking to reporters after briefing the allies, alluded to a major future role for the Organization for Security and Cooperation in Europe (OSCE) in verifying any Kosovo settlement.

And Solana, at his press conference, confirmed reports of an OSCE observer force in Kosovo of about 2,000 unarmed civilians that would be under NATO protection.

The developments followed a hectic day of shuttle diplomacy in Yugoslavia and saber rattling at NATO headquarters here. ``We see no reason to let up on the military pressure against Milosevic,'' an alliance official said lateTuesday night as Holbrooke was flying here from Belgrade.

``It is the feeling of the alliance that this is no time to relent. We need to keep up the pressure and make it clear to Milosevic that only full compliance will be acceptable, that a partial deal is no deal.''

The French ambassador to Macedonia, Jacques Huntzinger, was also in Belgrade on Monday to add to the eleventh-hour diplomatic efforts to persuade Milosevic to back down in Serbia's ethnic Albanian province, where separatists are fighting for independence.

At the UN headquarters in New York, UN spokesman Fred Eckhard said Milosevic had told UN Secretary General Kofi Annan that he was trying to comply with UN demands to end the violence in Kosovo.

Milosevic told Annan by telephone Monday that he ``was in the process of complying, or trying to come into full compliance'' with Security Council resolutions, said Eckhard.

NATO diplomats said Milosevic had agreed to an OSCE on-the-ground surveillance force under NATO protection.

And, thysaid, he agreed to make a unilateral declaration on Kosovo autonomy.

The hopeful signs continued when Milosevic later said: ``The necessary conditions exist for a peaceful and political solution to the problems in Kosovo.''