ONE substantial left-over problem from the Balkan wars of the 1990s is the future of Kosovo, once part of Serbia but for the last seven years administered by the United Nations. The problem about its future is that the majority of Kosovans are ethnic Albanians who want Kosovo to beome an independent state while the minority Serbs want the restoration of their historic link with Belgrade which was cut by NATO's 78-day bombing campaign. Basically the Albanian and the Serb people of Kosovo do not live together in the same villages and prefer not to speak to each other. Earlier this week the United Nations held a summit meeting in Vienna to see whether some acceptable form of co-habitation could be devised wihout actually determining the issue of sovereignty. At the end of the meeting the UN mediator, Martti Ahtisaari of Finland, told the press: “There has been no progress. I would be lying if I said there had been.” The Serbian prime minister, Vojislav Kostunica, and his delegation did not turn up at a luncheon to which both sides had been invited. This week's meeting followed some six months of lower-level negotiations which proved unproductive. However, Mr Ahtisaari believes that if the two sides will not negotiate it will be necessary to impose some form of UN settlement. The five countries forming a Contact Group on Kosovo, Britain, France, Germany, Italy, Russia and the United States, want a solution to be found by the end of this year.