The broad ingredients of the deal reached with Yugoslavia over Kosovo are clear, and amount to a total victory for Nato.

But, as always in the Balkans, the actual application of any settlement matters more than grand principles.

Western governments remain justifiably suspicious of President Milosevic's good faith in applying the deal.

Paradoxically, however, this now matters less; having made the vital concession of abandoning control over Kosovo, the Yugoslav leader cannot go back on his word partly because his population is weary of the war and partly because Mr Milosevic's main task is to survive at home.

The Milosevic regime

The Milosevic regime relied on a classic Balkan mixture of chicanery and nepotism, kept together with divide-and-rule techniques.

The military and the security services were kept at loggerheads; nationalist politicians were pitted against democratic opposition leaders.

But all these forces which President Milosevic was careful to keep apart are now uniting in opposition to the regime.

The armed forces were led by the president into four wars this decade, and four straight defeats; the nationalists accuse the Yugoslav leader of betrayal, while what is left of Serbia's democratic opposition knows that the country will have no hope of emerging from its international isolation and economic misery as long as President Milosevic remains in power.

A simple headline in Belgrade: "It's over"

The ruler in Belgrade may get an immediate respite as the armed forces regroup and lick their wounds, and the population is temporarily relieved from the daily air attacks.

Yet this lull is unlikely to survive for long; Mr Milosevic knows that he can no longer create much trouble in Kosovo, and defend his back against coup plotters in Belgrade.

In short, he has cut his losses with Nato, in the hope of saving his skin at home.

The withdrawal process

This does not mean that Nato can expect a smooth operation, for many of the details of the deal still need to be worked out.

The first concerns the withdrawal of Yugoslav troops, the precondition before the peace operation can begin.

Nato will try to make sure that the withdrawal is speedy, complete and verifiable; Alliance commanders worry about Serb troops which may stay behind under the guise of civilian bodies, or minefields which will not be notified to the incoming Western forces.

Yugoslavia's generals, on the other hand, will try to lengthen the period of withdrawal, if only because much of their deployment in Kosovo has been in small units which require time before regrouping.

Belgrade will also be seeking reassurances that neither Nato nor the KLA, the ethnic Albanian guerrilla organisation, will target the withdrawing Yugoslav convoys; any army is at its most vulnerable in such an operation.

Solutions will be found, mainly by introducing Western liaison officers on the ground immediately, and restricting the Yugoslav withdrawal to specified corridors which will not be attacked from the air.

But the Alliance cannot promise Yugoslavia that the KLA will refrain from an offensive, and the KLA fighters have every interest in doing precisely that.

Delicate operation

In order to prevent a void, Nato will have to march into the province very quickly.

Up to 30 countries (both within and outside the Alliance) have pledged troops for an international force which will rise to 50,000 troops, more than the Yugoslavs themselves considered necessary in order to hold Kosovo.

The snag is that, with the notable exception of Britain, not many of these troops are actually positioned in neighbouring countries and ready for action.

The chances are that Nato will have to send in an advance party, with all the risks which such an operation may entail.

Just about the worst outcome is one in which Kosovo slides into warfare between various KLA bands and the retreating Yugoslav forces, while Nato has no power to stop either.

A botched takeover of Kosovo will not only be embarrassing for the Alliance, but may also increase the tensions between Nato and the KLA which are already bubbling below the surface, and reduce the chances of a refugee return to the province, another urgent Nato task.

Russian concerns

And then there is the delicate matter of the command structure for the entire operation.

The West assumes that the entire force will operate under a unified command. In theory, this means that Russians will not be able to have their own sector in Kosovo, and that the province will be kept as a whole.

But it stretches credulity to believe that Russian generals will simply consent to take orders from Nato commanders and, even if they did, much of the Russian military equipment and communications is not compatible with that of the Alliance.

The result may be that, although Russians will operate alongside Nato troops, Moscow's soldiers will still be confined to one part of the province.

If this happens, refugees will refuse to return to that area, and a division of Kosovo will take place, almost by default.

In order to prevent this, Nato will need to establish a rotation of forces, just as it is trying to assemble the troops in the first place.

UN approval

And, if these problems were not enough already, a UN mandate for the operation will have to be approved by the Security Council in New York.

Serbs will have to deal with the bitter legacy of Nato's strikes

Russia and China will not vote on this mandate before Nato has suspended the air offensive against Yugoslavia, while Nato cannot suspend the operation until it is sure that a large number of Yugoslav troops has left the province.

Meanwhile, as the diplomatic pirouette continues in New York, neither Russia nor China are likely to reveal their true positions.

Despite the undertaking given by Viktor Chernomyrdin, the Russian Balkan negotiator, that Russia will operate under one command, Moscow is still demanding to run its troops in parallel to those of Nato.

Furthermore, President Clinton may encounter difficulties with his Republican-controlled Congress if the operation in which roughly 7,000 US troops will take part is put under a UN umbrella.

And, finally, Nato wants a very loose UN mandate which will allow local Western commanders considerable scope for action, while the Russians and the Chinese are likely to insist on a tightly-drafted, prescriptive international mandate, which still upholds the principle of Yugoslav sovereignty over Kosovo.

Only when all these issues are solved the true nature of the Kosovo operation will become clear. And it is only then that Nato may be entitled to proclaim victory.

Winter approaching

But the task of stabilising the Balkans is just beginning. Serbia has suffered terribly during the war; Western intelligence estimates put the country's economic losses alone at roughly $100bn.

The country will remain a disaster in the Balkans, and may yet turn into a new humanitarian crisis by this winter.

Having experienced large flows of ethnic Albanian refugees, Europe may be about to encounter Serb refugees as well.

The strategic void created by Serbia's virtual collapse may not be important for the region as a whole, at least as long as large Western military formations remain in the Balkans.

Nevertheless, Macedonia, with a large ethnic Albanian minority and fearful that it may be the subject of another territorial division, will draw closer to Serbia.

Stability under threat

Trouble could also arise if Montenegro, a component part of Yugoslavia, decides to become independent and asks for Western assistance.

In the long term, the region's stability will depend on the economic reconstruction plans which are now being put together.

If even a fraction of the grand proposals currently being discussed by the German presidency of the European Union materialise, then the Balkans can look forward to some peace.

But if the West remains concentrated on the immediate crisis in Kosovo, it will quickly discover further troubles throughout the region.

At the very best, the Kosovo deal is just as small step on the long march towards regional stability.