Leaders of ethnic Albanian rebels in south Serbia yesterday signed a ceasefire with Belgrade that ends a year of fighting and marks a breakthrough in NATO's efforts to halt the spread of ethnic conflict beyond the borders of UN-run Kosovo.
In separate ceremonies, the Belgrade delegation and the rebel chief, Mr Shefket Musliu, signed the accord after the Albanian gunmen dropped objections to Yugoslav troops deploying in part of a neutral buffer zone the rebels hold.
The signing was a success for NATO, tasked with security in post-war Kosovo but struggling to contain the aftershock of the bloody ethnic conflict in which it was forced to bomb Yugoslav forces out of the Serbian province.
"This is a major step forward. . . the whole process is now moving forward," said NATO's Balkans envoy, Mr Peter Feith, after the rebels inked the document in their stronghold of Konculj in the buffer zone between Kosovo and the rest of Serbia.
Yesterday's signing was the result of intensive shuttle diplomacy at the weekend by Mr Feith, as Belgrade refused to deal directly with "terrorists".
NATO feared the rebellion, which had already flared up in neighbouring Macedonia last month, could drag the whole region into a new Balkans war.
If international monitors are satisfied in a week that both sides have respected the ceasefire in the wooded hill country, the two sides plan to open talks on the future of the impoverished region.
The rebels want a referendum on whether the Presevo Valley, home to 70,000 ethnic Albanians and around 30,000 Serbs, should remain under Belgrade's control. But Belgrade's own peace plan sets out far greater political involvement for the Albanian community, as well as demilitarisation and a major aid package, but stops short of autonomy. The Albanian rebel force first appeared in January 2000 after Serbian police allegedly shot dead two Albanian brothers in a village in the demilitarised buffer zone, set up by NATO in June at the end of its air war against Yugoslavia.
The rebel ranks quickly swelled in the last months of the rule of the former Yugoslav president, Mr Slobodan Milosevic, as local men and volunteers from Kosovo fought for autonomy or even union with Kosovo.
Since Mr Milosevic was ousted in October last year, the international community has tried to consolidate his democratic successors, in particular by defusing the armed insurrection they inherited in the south.
The rebels stepped up their armed campaign in November as international sympathy swung sharply from the Albanians to newly democratic Belgrade. In a lightning offensive, the guerrillas drove Serbian police - the only force allowed in the zone - out of the border strip.
International fears about the region rose sharply last month with the emergence of a similar Albanian rebel group in northern Macedonia, which Belgrade and Skopje charged was allied with the first and aimed to destabilise the Balkans.
They said the long-term aim of the Albanian nationalists was to redraw regional boundaries to bring Albanian groups under the wing of an independent Kosovo, while also commanding a key Balkans trade route running through southern Serbia.
Last week, the alliance got tough with the rebels fighting Macedonian forces, shooting and injuring two gunmen and conducting a joint operation with Macedonian forces to occupy the rebels' base on the Kosovo-Macedonia border.
And last week, NATO gave the green light to its former foe to enter a small area at the southern tip of the buffer zone, where Kosovo, Serbia and Macedonia converge.
After signing up to the deal, the rebels still expressed reservations and insisted on the right to defend themselves if fired upon. One rebel chief, Cmdr Shpetimi, said: "The deployment of Belgrade's forces remains a problem. We will respect the ceasefire but we will not assume responsibility for areas where the army is deployed in the buffer zone."
Gen Carlo Cabigiosu, head of the NATO-led peacekeeping forces in Kosovo, said Yugoslav forces could enter the zone in "a matter of days". But the rebel leader, Mr Musliu, warned: "I and my commanders do not accept any responsibility for the spontaneous acts by local Albanians" in the sector where the Serbian forces are to deploy.