Serbia on Tuesday broke off talks held with Kosovo under European Union auspices to protest an operation by NATO peacekeepers in Kosovo against Serbs blocking a contested border, DPA reported.
"For the time being, the priority is the situation at border crossings, and for us no other topic exists," Serbia's chief negotiator, Borko Stefanovic, was quoted by Belgrade media as saying.
"I think in this situation it is unrealistic to talk about energy, telecommunications and regional initiatives," he said in Brussels, where he was meeting with EU mediator Robert Cooper and US representative Philip Reeker.
The seventh round since March of EU-facilitated talks between Serbia and Kosovo to resolve issues stemming from Kosovo's secession were scheduled without the disputed border crossings on the agenda.
The EU has set progress in the talks as a crucial condition for Serbia to be formally recognized as an EU membership candidate already this year. Belgrade officials had hoped that a date for the start of accession talks would be set at the same time.
The negotiations were already interrupted in July, when Serbia refused to lift a de-facto trade embargo on Kosovo goods.
That escalated into a trade war and tensions in northern Kosovo, when Pristina attempted to take control of border crossings in the north, one of few areas where Serbs outnumber ethnic Albanians.
Tensions in the area again erupted into violence on Tuesday, when NATO peacekeepers (KFOR) moved to dismantle roadblocks that the Serbs erected in their enclave in protest at their loss of control over the borders in mid-September.
KFOR sealed several "alternate" routes, which the Serbs had opened toward Serbia proper to circumvent controls at the official border crossings.
At least four peacekeepers and seven demonstrators were injured in clashes.