Kosovo’s Government adopted its new constitution yesterday in a low-key ceremony intended to mark the handover of UN administrative power to Pristina and the EU.

The move was intended to cement the country’s independence and to complete the break-up of the former Yugoslavia after the conflicts of the 1990s. But Belgrade, backed by Moscow, insisted that it would never recognise Kosovo’s breakaway status, heightening fears of partition between the Serb-dominated north and the ethnic Albanians who make up about 95 per cent of the population.

In reality, a full handover of UN authority could take many months and it is expected to remain a key player in the Serb half of the northern city of Mitrovica, where the EU has struggled to establish a presence.

President Tadic of Serbia said he viewed the proclamation of the Kosovan constitution as illegal. “Serbia views Kosovo as its southern province,” he said. “It will defend its integrity by peaceful means, using diplomacy, without resorting to force.”

In a ceremony shunned by Slobodan Samardzic, Serbia’s top official for Kosovo, the Pristina Government played its new national anthem but without the nationalist words for fear of inflaming Serb anger.

Mr Samadzic instead visited Mitrovica where a gunman attacked a police station and wounded an officer on Saturday. He believes that the northern region which borders Serbia should have its own regional assembly — a move that observers feel would bring Kosovo closer to a partition along ethnic lines.

The UN has overseen Kosovo’s institutions since its brief war with Serbia in 1999 to halt the ethnic cleansing of the late former Serb ruler Slobodan Milosevic.

UN responsibility for helping the police and local government was mostly passed to the EU last week at Kosovo’s request but Russia said it considered the 2,200-strong EU mission illegal because it has not been approved by the UN Security Council.

Despite the Russian protests, Ban Ki Moon, the UN Secretary General, said last week that he intended to “reconfigure the international civil presence” in Kosovo “in keeping with the European Union’s expressed willingness to play an enhanced operational role in Kosovo in the area of the rule of law.”

He added: “The European Union will, over a period of time, gradually assume increasing operational responsibilities in the areas of international policing, justice, and customs throughout Kosovo.”

However, the UN is expected to continue to play a role in Mitrovica, further fuelling fears of an ethnic partition.

The Times understands that both Joachim Rucker, the German who runs the UN operation in Kosovo, and his American deputy, Lawrence Rossin, will step down and be replaced. This would be seen as a response to Russian concerns about Mr Rucker’s neutrality over the independence question.

Kosovo’s declaration of independence in February has been recognised by 43 UN member nations including Britain, the United States and Turkey. The EU remains divided with Spain and Romania among seven members refusing to acknowledge its legitimacy.

Oliver Ivanovic, a moderate Kosovo Serb leader, said: “For Albanians, the constitution probably means something but, for Serbs, absolutely nothing. It has lessened the possibility that Serbs and Albanians converge in the future.

“Serbs will be more inclined to turn to their parallel institutions, which could lead to more conflict.”

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