Kosovo, which is 90 percent ethnic Albanian, has been under UN administration since 1999, when NATO launched airstrikes to halt a Serbian crackdown on ethnic Albanian separatists.
NATO has more than 16,000 peacekeepers in Kosovo.
Internationally mediated talks on Kosovo's future broke down last year over the ethnic Albanian leadership's insistence on full statehood and Serbia's refusal to relinquish a land Serbs consider the ancient cradle of their state and religion.
Also see: ANALYSIS: Kosovo declaration raises issue of Taiwan's future
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