Patriarch Pavle, the head of the Church, urged the international community to abide in those negotiations by "principles of justice as the foundation of international law and order."
Independence for Kosovo would mean "it is possible to snatch away the territory of a democratic country in Europe before the eyes of the entire world," the Patriarch said in a televised address.
"Such an act of highjacking, as veiled as it would be, would still constitute occupation of sovereign Serbian land," he said.
The Church's warning, issued in a statement, and the Patriarch's television appeal Friday reflected the strongest support to date for the Serbian government position that Kosovo must not be split from Serbia, despite an independence drive by most of its majority ethnic Albanian population.
"A just solution can only be found through negotiations," the church statement said. "It (the solution) must not be one-sided and imposed ... because that would lead to a mass exodus of the population and fresh tensions in the Balkans with unforeseeable consequences."
Kosovo, formally a province in Serbia, has been run by the United Nations and NATO since 1999, when the Alliance bombed Serbia for 78 days to force it to end a crackdown against ethnic Albanian separatists.
The U.N. Security Council has approved the start of talks later this month to determine the province's future status.
Although it has had no authority over Kosovo for more than six years, Belgrade is hoping to keep at least formal control over the region, which most Serbs consider the cradle of their history and culture.
The Serbian Church, whose ancient seat and hundreds of medieval monasteries are located in Kosovo, has been a harsh critic of Western policies in the province.
The church said it has a "vital interest" to protect its holy places in Kosovo, and called for special protection zones around Serb religious sites in the province.
Dozens of Kosovo Serb religious monuments have been destroyed by extremist ethnic Albanians, most of whom are Muslims, since 1999. More than 200,000 Serbs and other non-Albanians fled the province in the face of attacks and harassment, AP reported. V.A.