"Frequent statements of U.S. officials in favor of Kosovo's independence lead to the deterioration of the Serbian-U.S. relations," Kostunica said in a statement.
"If the United States wants to develop good relations with Serbia, then it goes without saying that it must observe Serbia's territorial integrity," Kostunica said.
He added that Serbian officials had repeatedly made it clear that the preservation of territorial integrity was Serbia's top state and national interest.
Kosovo, with 90 percent of its population ethnic Albanians, has been run by the United Nations since 1999, when NATO bombings halted Serbia's crackdown on separatist Albanian rebels. Talks on Kosovo's future status between its Albanian majority and Serbian authorities were first officially launched in November 2005, but ended in vain 13 months later.
U.N. Kosovo envoy Martti Ahtisaari has proposed internationally supervised independence for Kosovo, a move backed by the U.S., most EU countries and Kosovo Albanian leaders, but rejected by Serbia and its traditional ally Russia.
Kostunica, a moderate nationalist and a harsh critic of Western policies in the Balkans, has insisted that Washington had no right to give away Serbian territory.
During a visit to neighboring Albania earlier this month, U.S. President George W. Bush hinted that the U.S. could recognize Kosovo without the U.N. Security Council's consent, stressing that there cannot be endless dialogue about achieving independence for Kosovo.