MOSCOW, April 18 - RAPSI. The UK has not changed its position on the Litvinenko case, according to UK Ambassador to Russia Tim Barrow.

The ambassador said that certain decisions were taken after Litvinenko's murder and so far they have not been revised.

Ex-FSB agent Alexander Litvinenko fled to the UK in 2000. He died as a result of polonium-210 poisoning in London in November 2006. British officials claimed they had enough evidence to charge Russian parliamentary Andrey Lugovoy with the murder of the former FSB officer.

Lugovoy said the charges against him are politically motivated.

Former KGB officer Dmitry Kovtun has also been accused by the UK authorities of involvement in Alexander Litvinenko's death.

Kovtun confirmed earlier that Russian prosecutors had received a letter from the Crown Prosecution Service requesting his extradition to face trial. He believes that the request was made under the pressure of Litvinenko's wife, backed by self-exiled Russian millionaire Boris Berezovsky.

UK authorities placed Kovtun on the international wanted list for his involvement in the crime.

He intended to testify in the case by videoconference.

When the UK requested Lugovoys extradition, the Russian Prosecutor General's Office responded that it contradicts the Constitution, but it was ready to investigate into Litvinenko's death together with the UK authorities.

The Litvinenko case has seriously damaged the Moscow-London relations. The UK reacted to the Lugovoy extradition refusal by expelling four Russian diplomats. Russia in turn deported four British Embassy employees.

During UK Prime Minister David Cameron's visit to Moscow in September, both parties stated that their positions on the Litvinenko case remained unchanged.