Amid a growing diplomatic row that threatens to affect the European Union's ties to Russia, Moscow said it intends to put a halt to cooperating with London on counter-terrorism and security matters.
Moscow has threatened to retaliate after London expelled four Russian diplomats
The move, announced in Moscow by Deputy Foreign Minister Alexander Gruschko on Tuesday, follows Britain's decision to expel four Russian diplomats over Moscow's refusal to extradite Andrei Lugovoi, suspected of murdering Kremlin critic and British citizen Alexander Litvinenko.
Gruschko also warned that Russia would be implementing an "appropriate response" to counter the British move, which was announced by British Foreign Secretary David Miliband on Monday.
Gruschko said Britain was trying to "punish Russia for observing our own constitution", the Russian news agency Interfax reported.
"It is apparent that the (British) sanctions are aimed at politicizing the Litvinenko affair," he added. "This is a direct path to confrontation."
EU could be pulled into fight
Russia has promised to respond to the expulsion
Gruschko also said he hoped the European Union would have "enough common sense" as to not allow itself to become an instrument in the affair.
But the EU is likely to be pulled into any dispute between a member state and Russia, according to Luxemburg's Foreign Minister Jean Asselborn.
"Naturally we are showing our solidarity with another EU member, but you also have to have the right to question certain steps," Asselborn told Financial Times Deutschland, adding that he wondered if the dispute could have been settled using "silent, diplomatic channels."
German Chancellor Angela Merkel gave her support to Brown's decision to expel the Russians, who are rumored to be part of the embassy's intelligence unit.
"The decisions have been made after very careful consideration of the facts at hand in the United Kingdom," she said Monday night after meeting with Brown, who made Berlin his first foreign stop as Britain's prime minister. "We hope that this phase will be overcome as quickly as possible and that one can continue along the lines of having a very good cooperation, which is after all what you want with Russia."
The French Foreign Ministry allow issued a statement Tuesday calling for Moscow to "constructively answer the British request."
UK also refused to extradite Russians
Russia has demanded Britain extradite Chechen leader Ahmed Zakayev
Miliband told parliament Monday there was a "significant body of evidence" of Lugovoi's involvement in the Litvinenko murder, but Russia has refused to extradite him to face trial in Britain.
According to the British public prosecutor, ex-KGB officer Lugovoi is said to have killed former Russian agent Litvinenko by poisoning him with radioactive polonium-210 in November 2006. Lugovoi has denied involvement in the case.
The Russian government condemned the diplomats' expulsion as "provocative" and "immoral" and said it would have "the most serious consequences for Russian-British relations as a whole."
Grushko added that Britain has refused to extradite 21 Russians living in the UK and offered asylum to some of them.
"If Russia acted in the same manner as London, over 80 diplomats would have been expelled from the British embassy to Russia," Grushko said
Business ties unlikely to be hurt
Both the British and Russian governments emphasized that they did not anticipate their countries' economic relationship to suffer due to the political confrontation.
A stop to energy deliveries damage both Russia and the UK
"We do not expect our disappointment with the Russian authorities about the Litvinenko case to affect the economic sphere," British ambassador to Russia Tony Brenton told reporters. "Indeed we expect British-Russian economic ties to continue to grow."
Grushko said that Moscow would take international business interests into account when formulating its as yet unannounced response to the Russian diplomats' expulsion.
"We will fully take into account the interests of ordinary citizens, tourists, participants in cultural and scientific exchanges and business circles," he said. "We do not want them to suffer because of London's political actions."
Russia, which has used its vast energy resources as a political instrument to limit fuel supplies to its neighbors in the past, would benefit little from such action with Britain as the UK is one of the largest investors in Russian energy markets and pumped nearly 4 billion euros into the branch last year, according to a report in Britain's Times newspaper.
A spokesman for Britain's Foreign Office said no retaliation by Russia would be justified.