The premiers of Serbia and Kosovo went into tough talks Tuesday to defuse tension in one of Europe's last trouble-spots, facing EU demands for "concrete" signs of progress.
Serbian Prime Minister Ivica Dacic and Kosovo Prime Minister Hashim Thaci met separately and then jointly with EU foreign policy chief Catherine Ashton just 48 hours after the former Serbian province marked the fifth anniversary of its unilateral declaration of independence.
With Belgrade still staunchly refusing to recognise Pristina's independence, the European Union has brokered talks betweem the two sides since 2011 in a bid to deflate simmering tension between the Western Balkans neighbours.
"This is a crucial week," said European Commission president Jose Manuel Barroso as EU president Herman Van Rompuy warned that "concrete results in the dialogue are essential for progress on the EU path for both Kosovo and Serbia."
The 27-nation bloc is dangling a carrot of EU membership for Serbia and of closer ties with the bloc for Kosovo in hopes of accelerating a normalisation of ties between the two.
Serbia hopes to be given a date to start EU accession talks at a summit in June. European Commission president Jose Manuel Barroso said Kosovo too could win agreement in June to work on a special agreement bringing it closer to the bloc -- though not inside as five EU nations do not recognise it.
But Tuesday's closed-door face-to-face between the pair, which diplomats believe will likely continue into Wednesday, will tackle the most difficult problem holding up a deal -- the fate of 40,000 ethnic Serbs in northern Kosovo who refuse to recognise the Albanian authorities, as well as 80,000 others in enclaves scattered throughout Kosovo.
"This time it won't be easy to come up with a solution," said an EU diplomat speaking on condition of anonymity. "They might come up with principles and a few goal-posts but I don't think we'll see a full-fledged deal yet."
Kosovo foreign minister Enver Hoxhaj has said he hoped the two would clinch an agreement in Brussels that would open the door to elections smoothing the integration of the ethnic Serbs.
He also hoped the deal would eventually end the existence of parallel Serb institutions in the north of Kosovo, such as ethnic Serb police.
Dacic on the other hand told the Belgrade daily Vecernje Novosti as he headed to Belgium that this round of talks would be "the most difficult" and that he hoped to agree a plan to establish an association of Serb municipalities that would have "clear jurisdiction" over education and justice.
The police could maintain ties with both Belgrade and Pristina, he added.
But Thaci gave little sign of agreeing to Belgrade maintaining its reach within Kosovo.
"Kosovo is one," he said in Brussels, adding that "my goal is to build a new inter-state relationship between Kosovo and Serbia."
This month also saw the first talks between the Kosovo and Serbia heads of state, a significant step in two years of EU efforts to ease tension on its Balkans doorstep.
That meeting came nearly 14 years after the end of the 1998-1999 conflict between Belgrade and Kosovo's ethnic Albanian separatist guerrillas.
The two premiers, Serbia's Ivica Dacic and Kosovo's Hashim Thaci, have already met four times in Brussels since October, with Ashton as mediator.