Serbs in northern Kosovo have begun voting in a referendum asking whether or not they accept the authority of Kosovo's ethnic Albanian rulers.
Results of the two-day referendum are expected to be publicized on February 19.
Leaders from the European Union, other Western states, and even Serbia have urged Kosovar Serbs not to go ahead with the referendum.
Serbian President Boris Tadic said the vote would "not contribute to dialogue" between Belgrade and Pristina.
Serbia is seeking EU membership, and Brussels wants Belgrade to improve relations with Pristina.
The commander of NATO peacekeepers in Kosovo, General Erhard Drews, said the referendum could stoke violence by extremist Albanians.
Kosovo declared independence from Serbia four years ago.
It has been recognized by most Western states, but Belgrade, Russia, and Kosovo's Serbs refuse to do so.
It is estimated that over 100,000 ethnic Serbs live in Kosovo, with a large concentration in the north.
Compiled from agency reports