"Kosovo has its democratic institutions and has the right to decide about its prime minister," UN administration spokesman Neeraj Singh said.
Ceku, the former commander of the Kosovo Liberation Army, was made Kosovo's prime minister-designate last week.
Serbian authorities in Belgrade said last week that justice authorities were investigating Ceku for war crimes allegedly committed during the 1998-99 Kosovo war and had issued an international warrant for his arrest.
Serbian Prime Minister Vojislav Kostunica said last week that he expects the head of the UN mission in Kosovo to prevent Ceku from taking office.
The province formally remains a part of Serbia, but has been under UN administration since mid-1999, after a NATO air campaign that drove Serbian forces out of the province.
Spotlight On Kosovo
THE WORLD'S NEWEST NATION? The region of Kosovo has a population of more than 2 million, some 90 percent of whom are ethnic Albanians. It was one of the poorest regions in the former Yugoslavia, but has considerable mineral wealth and an enterprising population, many of whom work abroad but keep close contact with Kosovo. All ethnic Albanian political parties seek independence on the principles of self-determination and majority rule. They feel that Serbia lost its historically based claim to what was its autonomous province under the 1974 constitution by revoking that autonomy in the late 1980s and then conducting a crackdown in 1999 that forced some 850,000 people to flee their homes.
Since NATO's intervention that year to stop the expulsions, Kosovo has been under a UN administration (UNMIK). The UN has begun to gradually transfer functions to elected Kosovar institutions. The primary Serbian concerns are physical safety for the local Serbian minority, a secure return for the tens of thousands of Serbian displaced persons, and protection for historic Serbian religious buildings. The main problems affecting all Kosovars, however, are economic. Until Kosovo's final status is clarified and new legislation passed and enforced, it will not be able to attract the investment it needs to provide jobs for its population, which is one of the youngest and fastest growing in Europe. Prosperity is widely seen as the key to political stability and interethnic coexistence in Kosovo, as is the case in much of Southeastern Europe.
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