Deputy Prime Minister, Hajrudin Kuci said on Friday that both border crossings, Jarinje and Brnjak in the north of Kosovo, were to be controlled by Kosovo police and customs officers.

"Implementation of the operational plan of the government of Kosovo has started," Kuci told a local TV station.

"The plan has been fulfilled one hundred percent so far and it is important that there has been no any incident," Kuci said.

Serbs, who are the majority in the tense northern area, set up a blockade late Thursday the roads leading to two border crossings.

They moved their trucks to block the road near Jarinje, which had already been closed to traffic by NATO-led peacekeepers KFOR who have manned the post since July unrest in the area.

At another disputed border crossing, Brnjak, several trucks were parked across the road, with several dozen protestors gathered around, witnesses said.

In New York, a UN peacekeeping chief told a UN Security Council meeting on Kosovo the United Nations was "very concerned" that any operation at the border posts "could lead to another outbreak of violence" in Kosovo.

Russia's UN ambassador Vitaly Churkin told reporters that Moscow had information that the operation would be carried out with the assistance of KFOR, and an EU law and order mission, EULEX. Churkin warned that any operation could lead to "bloodshed".

The clashes in the north erupted in late July when the Pristina government dispatched special police to take over the two posts to enforce a ban on imports from Serbia that was imposed in retaliation for an earlier Belgrade ban on goods from Kosovo.

The Serbian ban was imposed in protest at Kosovo's 2008 declaration of independence from Belgrade, which Serbia, backed by Russia, has refused to recognize.