Before the Russian and EU peace envoys arrived here yesterday, Western leaders called on the Yugoslav President, Mr Slobodan Milosevic, to clarify what he meant by his recent acceptance of the G8 principles on May 6th for resolving the war. But it was the document's vagueness that ultimately made it possible for Mr Milosevic to endorse it.
Much of the confusion over the imminence (or not) of a peace deal last night derived from one question: must Yugoslavia accept NATO's five demands - as the US insists - before the bombardment can be stopped? Or is Belgrade's acceptance of the G8 principles sufficient?
Ultimately, it is a question of whether the US or Europe dictates the terms for ending the conflict, and Mr Milosevic can be counted on to try to divide them.
Europe has more at stake in the Balkan war, and with the exception of Britain, is more eager than the US to end it quickly. France in particular has insisted on a United Nations role.
Belgrade would much rather deal with the UN than with NATO. In a statement published here yesterday, Mr Milosevic said the war could be solved "above all by restoring the fundamental role of the United Nations".
Diplomats in Belgrade note that Mr Milosevic endorsed the G8 principles last week immediately after the International Court of Justice in The Hague indicted him for war crimes. They believe he saw the G8 principles as a way out of the crisis, and a way to stay in power.
The entire Serb leadership, including Mr Milosevic, is eager to end the war, which has destroyed much of Serbia's infrastructure, but not at any price. The Yugoslav President is now believed willing to accept almost any international force in Kosovo except US and British troops, the two countries which Belgrade holds most responsible for what it calls the "NATO aggression".
But Mr Clinton announced yesterday that the US would send 7,000 ground troops to Kosovo.
The Russian envoy, Mr Viktor Chernomyrdin, had suggested that US and British soldiers might stay on the borders of Kosovo, but Washington and London may not be willing to make such a concession.
Washington has apparently relented slightly on the question of whether Serb troops could remain in Kosovo, agreeing in principle to a face-saving token force, perhaps to guard ancient Orthodox monasteries.
Mr Chernomyrdin's allusion to separate Russian and NATO sectors in Kosovo has revived speculation here that the war will end with the de facto partition of Kosovo. The assumption is that Russians would be stationed in the northern, mineral-rich part of the province, which also holds the greatest concentration of Serbs.
Kosovo was partitioned between Germans and Italians in the second World War, and Serb nationalists have accused NATO of wanting to repeat history. Albanian refugees could not be expected to return to a Russian-controlled zone, because Russia is regarded as an ally of Serbia.
If nothing else, the mission of Mr Ahtisaari and Mr Chernomyrdin will have brought Belgrade a reprieve from the bombing, as NATO ceases attacks on the capital while important envoys are present.