British Foreign Secretary David Miliband announced on Monday that Britain will expel four diplomats from Russian embassy in London in response to Russia's refusal to extradite Andrei Lugovoi accused by Britain of murdering former KGB agent Alexander Litvinenko.

Speaking at the House of Commons, Miliband said "This is a situation the government has not sought and does not welcome. But we have no choice but to address it."

Britain would need "an appropriate response" due to Russia's failure to cooperate to find a solution, said he.

"Our aims are clear: first to advance our judicial process, second to bring home to the Russian government the consequences of their failure to cooperate and third to emphasize our commitment to promoting the safety of British citizens and visitors," said he