During their brief stay in the capital, Pristina, Mr Cook and his colleagues, Joschka Fischer of Germany, Lamberto Dini of Italy and Hubert Vedrine of France, will hold talks with General Sir Michael Jackson, commander of the K-For peacekeeping force, ethnic Albanian leaders and - if possible and perhaps most important - representatives of the fast-dwindling Serb community.
The Foreign Secretary will also visit Velika Krusa, the site of one of the worst Serb atrocities, involving the massacre of up to 105 ethnic Albanians,where British forensic investigators are now at work.
It was still uncertain whether a meeting with the Serbs would be arranged. But psychologically it could be crucial to Nato's efforts to portray itself as even-handed. Only this offers a realistic chance of halting the the flight of tens of thousands of Serbs who are terrified of reprisals by the ethnic Albanians after the withdrawal of the Yugoslav army.
Given all that has happened, and the perception among Serbs that Nato is their enemy, this will be a hard task indeed. But Britain is taking some surprisingly favourable comment about the peacekeeping operation in the official Serb media as a signal that Belgrade is desperate to persuade them to stay in Kosovo - not just to keep a foothold in the province seen as the cradle of the nation, but also to ease strains on a Serbia battered and further impoverished by 11 weeks of bombing.
The trip by the quartet (though some doubt surrounded Mr Vedrine's participation last night) will be the first to Pristina itself by senior Western ministers since the end of the war. Mr Cook will also visit Macedonia and Albania, to stress the EU's intention to help two countries that bore the brunt of the refugee crisis. Mr Cook will thank them for their logistic support in the war - especially difficult for Macedonia, whose Slav majority was sympathetic to President Milosevic.
No major new aid initiatives are likely to be announced today. These await two important donors' conferences, in July and the autumn, and the fleshing out of the promised Balkan "stability pact". But the ministers will give assurances of the EU's determination to broaden co-operation and trade with both countries. The process will be easier with Macedonia than Albania, in whose northern parts virtual anarchy prevails.Reuse content