A letter by United Nations Secretary General Ban Ki-moon announcing plans to "reconfigure" the UN mission in Kosovo was passed to Kosovo President Fatmir Sejdiu on Thursday.
"We're reconfiguring in the light of the situation on the ground," a diplomat in Pristina told Deutsche Presse-Agentur dpa.
Sejdiu was expected to reveal more details to reporters later Thursday, amid legal and diplomatic uncertainty how the UN would downgrade its role to allow local authorities and a new, European Union mission more power.
Albanian media say the UN Mission, which took charge in Kosovo after NATO ousted Serbian forces in 1999, would gradually downsize by 70 per cent from Sunday, when Kosovo is due to pass its first sovereign constitution, following its unilateral declaration of independence on February 17.
Helping Kosovo and its 90-per cent Albanian majority along its first independence steps is the EU law-enforcing mission, EULEX, which is to take over some of the functions from UN, with others transferred to Kosovo institutions.
UNMIK is to remain longer in Serb enclaves, the largest of them on a quarter of Kosovo's territory in the north, where the local population joins authorities in Belgrade in opposing the presence of EULEX, arguing that Kosovo is Serbian soil.
Serb protests against Kosovo's declaration of independence have turned violent in the northern Mitrovica enclave, claiming the lives of one Ukrainian policeman and a Serb protester.
Another letter by Ban was sent to Belgrade and President Boris Tadic, but his cabinet could not confirm its arrival.
Changes to the UN mission and the arrival of EULEX have no effect on the NATO-led peacekeeping mission in Kosovo, the mission commander, General Xavier Bout de Marnhac, said.
"The reconfiguration ... doesn't change the KFOR mandate much, we're are still under (UN resolution 1244)," he said. "Now we have to see how to settle things for the next stage. I know the letter arrived, but haven't seen it yet."