By MIKE CORDER
Associated Press Writer

THE HAGUE, Netherlands (AP) - A decade after NATO airstrikes ended Serbia's bloody crackdown on its rebellious province, Kosovo told the U.N.'s highest court Tuesday its independence is irreversible and warned that any attempt to cancel it could set off a renewed conflict.

Serbia, noting that the case is the first attempt in the blood-soaked history of the Balkans to peacefully resolve a dispute, said Kosovo's unilateral independence tore at the very fabric of Serb national identity and breached international law.

The 15-judge International Court of Justice is being asked to render its legal opinion on the validity of Kovoso's February 2008 independence declaration, which has been recognized by 63 countries but not by the Security Council.

The opinion has no binding effect, but other countries with potential breakaway regions, like Spain with its Basque district, are closely watching the outcome.

Serbia's ambassador to France, Dusan Batakovic, said Kosovo's self-claimed independence challenged his country's sovereignty and undermined international law by breaching U.N. Security Council resolutions that set up a U.N.-backed provisional administration in Kosovo.

"Kosovo is the historical cradle of Serbia and constitutes one of the essential pillars of its identity," Batakovic told the court. Kosovo's declaration "is a challenge to the international legal order, based as it is on the principles of state sovereignty and territorial integrity."

Kosovo Foreign Minister Skender Hyseni told the court it would be "inconceivable" to reopen negotiations with Serbia on Kosovo's future.

"That would be highly disruptive, and could even spark new conflict in the region," Hyseni said.

Hyseni said former U.N. special envoy Martti Ahtisaari had recommended that Kosovo be granted independence and his plan was supported by the European Union, NATO and U.N. secretary-general.

Another of Serbia's lawyers, Malcolm Shaw, said Kosovo's recognition by other nations was irrelevant. The UnitedStates and most European Union states are among those that have recognized Kosovo's independence. Serbia, backed by Russia in the U.N. Security Council, and a majority of world's states are against the recognition.

"What is illegal cannot subsequently be rendered legal by the action of third parties," Shaw told the judges.

He warned if the court's opinion is seen as weakening the principle of a state's right to its territorial integrity, that "would be a source of considerable apprehension" for other countries facing secessionist movements.

The world court, the U.N.'s highest judicial body, likely will take months to reach its decision.

NATO bombed Serbia for 78 days in 1999 to end a brutal crackdown by the forces of then-President Slobodan Milosevic against Kosovo's separatist ethnic Albanians. Some 10,000 ethnic Albanians were killed and close to a million forced from their homes. Hundreds of Serbs were also killed in retaliatory attacks by Kosovo separatists.

Batakovic said Serbia "condemns and severely regrets" the violence unleashed by Milosevic's administration, but said Serbs are still being targeted today in Kosovo.

After Serbia and Kosovo's presentations on Tuesday, 29 other countries including all five permanent Security Council members will each get 45 minutes to present their arguments in hearings that will wrap up Dec. 11.

The case marks the first time China has ever addressed the court.

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