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MOSCOW - Russia has urged Britain not to politicise the row over its refusal to extradite the key suspect in Alexander Litvinenko's murder, saying it should be dealt with strictly as a legal case.
British officials have threatened unspecified steps against Russia for refusing to extradite Andrei Lugovoy, a former state security agent, to stand trial over the poisoning of Litvinenko in London last year.
One of the options available to London is to expel Russian diplomats -- a possibility which revives memories of Cold War days and has alarmed officials here.
"If it is confirmed, as the British media report, that the British foreign ministry is dealing with it (Lugovoy's case), it becomes a political issue," Russian Foreign Minister Sergei Lavrov told reporters.
"This case is a criminal one and should be dealt with by corresponding authorities ... we do not want to see it as political."
British Prime Minister Gordon Brown's official spokesman condemned Russia on Tuesday for refusing to extradite Lugovoy, saying its response was "extremely disappointing".
London's strong language has irritated Russian officials, who point out that their constitution prohibits the extradition of nationals.
A senior pro-Kremlin legislator said London's reaction was "entirely inappropriate".
Konstantin Kosachyov, chairman of the State Duma committee on international affairs, said that if reports on the possible expulsion of Russian diplomats were true, "it would mean a failure of Britain's policy towards Russia for many years to come and the British side will bear the full responsibility".
Litvinenko, a former employee of Russia's Federal Security Service who became a critic of Russian President Vladimir Putin, died an agonising death after ingesting a lethal dose of the rare radioactive substance polonium 210.
Traces of polonium were found in locations frequented by Lugovoy before the killing but the former agent has always insisted he is innocent, saying British intelligence or anti-Kremlin emigres probably murdered Litvinenko.
Britain has rejected a Russian offer to put Lugovoy on trial at home, saying it doubts Moscow's promises of a fair trial.
- REUTERS