"The Baden conference marks the end of troika-sponsored face to face negotiations", Mr Ischinger added, according to AFP.

Kosovo's president Fatmir Sejdu reaffirmed that Kosovo's independence "will happen very quickly", although he stopped short of giving an exact date.

It is believed, however, that former Kosovar guerilla leader Hashim Thaci, who won the legislative elections earlier this month, aims at declaring independence unilaterally by February 2008.

But Serbian president Boris Tadic said that Belgrade would use all legal and diplomatic measures to "annul" any decision that would grant Kosovo its own state.

"Serbia will not accept independence of Kosovo", Mr Tadic was cited as saying by AFP, adding his country "does not want violence".

But despite such claims, the US envoy for Kosovo Frank Wisner has warned the "peace of the Balkans is very much at stake".

"It is a volatile region", Mr Wisner was cited as saying by the Financial Times, adding "we're going into a very difficult time (..) The status quo over Kosovo is not sustainable".

It is believed that Washington would recognise Kosovo's unilaterally declared independence, but the move would certainly split the 27-nation bloc.

Five out of the 27 member states are firmly opposed to this scenario, according to EU diplomats.

Meanwhile, Moscow has once again thrown its support behind Serbia, with Russian foreign minister Sergei Lavrov saying "we cannot accept the incantation that this is a unique case, that independence is unavoidable".

Mr Lavrov described the situation as "very alarming" and added that "it is only now that many of those who supported calls for a speedy proclamation of Kosovo's independence are starting to understand the possible consequences", AFP reports.