Serbia's outgoing Prime Minister Vojislav Kostunica on Thursday rejected a plan to restructure the UN mission in Kosovo, state-controlled Tanjug news agency reported.

'Such a plan is opposite to the (United Nations Security Council) Resolution 1244 and therefore could not be acceptable for Serbia,' Kostunica was quoted by the agency as saying.

The resolution, adopted in mid-1999, ended war in Kosovo and imposed UN administration in the southern Serbian province.

Earlier in the day, the UN Secretary General Ban Ki-moon unveiled the plan to restructure its mission to Kosovo after nine years and hand over much of the responsibilities there to the European Union.

The move paves the way for the deployment of a vast EU police and justice mission, EULEX.

'(The) Serbian parliament in December passed a resolution saying that the EULEX mission... would jeopardize sovereignty, territorial integrity and (the) constitutional order of the Republic of Serbia,' Kostunica said.

The UN plan came as Kosovo was preparing to adopt a new constitution despite Serbian and Russian anger.

Kosovo -- with an overwhelmingly ethnic Albanian population -- unilaterally declared independence from Serbia on February 17. It has been recognized by more than 40 countries, including the United States and most members of the European Union.

The UN has run the territory since 1999 when a NATO bombing campaign ended a Serb crackdown on ethnic Albanian separatists.