State news agency Tanjug quoted Kostunica as saying he "no longer trusts his coalition partners, the Democratic Party and G17 Plus party, to be sincerely fighting to preserve Kosovo," which declared independence from Serbia on February 17.
"The government is in deep crisis, because there has been no readiness to firmly together insist that Serbia can become an EU member only as an integral state, with Kosovo," Kostunica said. "Over the next few days, parties must agree on a way out."
In the latest sign of a coalition split, Kostunica's bid to rule out any deal on closer EU ties until the bloc revokes the independence of Kosovo was overruled 2-to-1 on Thursday by his Democratic and G17 Plus partners, who said a parliamentary motion to that effect would drive the country into isolation.
It was the liberals' strongest challenge to Kostunica's policy of 'Kosovo above everything', after months of allowing him to make anti-Western statements and stoke nationalist feeling over Kosovo.
Kostunica has already recalled ambassadors from Washington and European capitals that recognized Kosovo, and wants to cool ties as long as the EU insists on sending a supervisory mission to guide the territory to full statehood.
But the Democrats of President Boris Tadic and their allies don't want to go as far as freezing Serbia's EU membership bid, for fear of reviving the image Serbia had in the 1990s when it was a pariah state because of its role in the Yugoslav wars.
Looking for an alternative to the EU, Kostunica has pushed for closer ties with Russia, Serbia's only big-power ally, personally insisting on a major energy sector deal with Moscow.
Hardline politicians in Serb-dominated north Kosovo on Friday urged Kostunica to scrap his current partners and go with the Radicals.
"Kostunica...if he wants to keep Kosovo, must form a new government with new coalition partners," Kosovo Serb leader Milan Ivanovic told reporters in the Serb stronghold of north Mitrovica, which rejects the rule of Kosovo's Albanian majority.
Güncelleme Tarihi: 07 Mart 2008, 16:23