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BELGRADE, March 17 Serbia and its ally Russia are consulting on joint steps to stop "all forms of violence against Kosovo Serbs", Serbia's caretaker prime minister Vojislav Kostunica said in a statement on Monday.
He accused NATO of "implementing a policy of force against Serbia" following clashes between alliance-led troops and Kosovo Serbs in the flashpoint Kosovo town of Mitrovica, the worst violence since Kosovo's secession one month ago.
"We have started the necessary consultations with Russia about a necessary joint reaction in order to stop all forms of violence against Serbs," his statement added.
It raised the prospect of Serbia inviting Russian troops into Serb-dominated northern Kosovo as peackeepers, undermining the authority of the NATO-led KFOR peacekeeping mission, creating potential for conflict, or heralding a partition of the territory.
Russia, which has repeatedly condemned Kosovo's independence as illegal and blocked it at the United Nations, has warned the Western backers of Kosovo's 90 percent Albanian majority that they are playing with fire.
Moscow has said it will not stand idly by and watch Kosovo Serbs oppressed. Kostunica "strongly condemned the use of force against Serbs who are opposing the introduction of a false state on Serbia's territory", the statement said.
It said the United Nations Security Council "has full responsibility to ensure security for Serbs in Kosovo, in accordance with Resolution 1244".
The U.N. in Kosovo says Serbia has a very selective approach to Resolution 1244, applying only those parts which suit its agenda and ignoring the parts that say NATO is mandated to keep the peace.
Monday's clashes involved U.N. police and KFOR troops from several countries.
Russia was a member of KFOR in the first four years after Serbian forces were expelled by NATO in 1999 in order to halt ethnic cleansing and the killing of Albanian civilians during a counter-insurgency war.
(Editing by Richard Balmforth)