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MOSCOW - Russia expelled four British diplomats overnight and suspended cooperation with London on fighting terrorism, as a bitter row over Moscow's refusal to extradite a murder suspect escalated.
The Kremlin said Russia had been forced into a "proportionate response" after Britain threw out four Russian diplomats earlier this week.
Foreign Ministry chief spokesman Mikhail Kamynin told reporters the British ambassador had been summoned and handed a note about "the unfriendly actions of Britain towards Russia".
"Four British embassy staff in Moscow are now persona non grata and they should leave the territory of the Russian Federation within 10 days," Kamynin said.
Britain called the expulsions "completely unjustified" and said it was disappointed Moscow had not signalled any fresh cooperation in the case of Alexander Litvinenko, a former Russian security agent murdered in London last year.
The United States and the European Union both weighed in with declarations of support for Britain and asked Russia to reconsider its refusal to co-operate. Moscow says its constitution prohibits the extradition of its citizens.
British prosecutors have charged Andrei Lugovoy, a former KGB bodyguard, with killing Litvinenko by spiking his tea with lethal radioactive polonium in a London hotel. Lugovoy denies the allegations.
Russia will also stop issuing visas to British officials and cease cooperation with London in the war on terror, Kamynin said, adding that Russia's response was the "minimum necessary".
Relations between the two former Cold War foes have chilled to the frostiest level since the collapse of the Soviet Union in the wake of Moscow's refusal to extradite Lugovoy, the latest in a series of irritants in bilateral relations.
"Russia was forced to give this proportionate response to the actions of the British authorities ... which we think are inopportune, provocative, amoral and short-sighted," said Kremlin deputy spokesman Dmitry Peskov.
"So the only signal we wanted to send is that we were forced to take these measures, but at the same time Russia proceeds from the need for good and constructive cooperation in all areas and with all states, including Britain," he said.
Russia and Britain are no strangers to tit-for-tat expulsions, which were common in Cold War days, but they were generally over spying cases. The last time diplomats were expelled was in 1996.
Analysts in Moscow said Russia had reacted with relative restraint to Britain's moves and noted official statements emphasising a desire not to affect business ties between the two nations, which are booming.
US Secretary of State Condoleezza Rice said on Thursday Russia should honour the British extradition request and "co-operate fully" and the EU presidency expressed disappointment at "Russia's failure to co-operate constructively".
Russian officials have responded indignantly to suggestions that they should change their constitution to accommodate the extradition request, pointing out that Britain has turned down several Russian extradition requests in recent years.
Lugovoy has appeared numerous times in front of the media in Moscow, where he runs a security business, insisting he is innocent and accusing British intelligence of having a hand in Litvinenko's agonising death.
- REUTERS