Russia criticised Britain yesterday for failing to allow its officials investigating the murder of Alexander Litvinenko to travel to London to interview witnesses.

Yury Fedotov, the Russian Ambassador, said that three weeks after relaying a request from Moscow to the Home Office for permission for Russian detectives to visit London, he had still not received an answer.

“The Russian side cooperated with Scotland Yard. They expect the same degree of cooperation,” he said at a briefing at his residence in Kensington.

“I’ve forwarded a letter from the Office of the Prosecutor-General [in Moscow] to the Home Office three weeks ago and for the time being no Russian investigators are in London.

“When British investigators asked to go to Moscow they did it Saturday morning and Monday morning they were in Moscow already.”

Part of the problem could be that the Prosecutor-General’s letter setting out how they intend to proceed with their investigation runs to 105 pages, all in Russian.

The Russian investigation also poses a delicate diplomatic problem for the British authorities. Scotland Yard detectives were allowed to travel to Moscow and interview witnesses, including figures suspected of involvement in the poisoning of the former Russian intelligence officer with polonium210. The Kremlin has denied any involvement in the murder. There are fears that Russian investigators will seek to shift the focus of the investigation away from Moscow and towards Litvinenko’s contacts in the Russian exiled community in London.

Boris Berezovsky, a billionaire businessman and outspoken opponent of President Putin, is expected to be high on the list of people the Russian detectives will want to question.

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