How Europe deals with Serbia will be a question that gains increasing prominence over the coming months. Dealing with the Kosovo issue is bound to strain ties as will the possible election to the Serbian presidency of an ally of the late autocrat Slobodan Milosevic.

Tomislav Nikolic of the ultranationalist Serbian Radical Party, which backed Milosevic during his Balkan war campaigns in the 1990s until the former president's ouster in 2000 in a popular uprising, is in pole position to beat President Boris Tadic, soft-spoken leader of the pro-Western Democratic Party.

Western nations are likely to shun Nikolic if he is elected, given his threats to sever ties with any capital that recognises Kosovo's independence if it breaks away.

But threat and counter-threat must not be the basis for policy by either Belgrade or Brussels. The Serb electorate has a clear choice but Brussels must keep lines of communication open to Belgrade.