Litvinenko widow demands justice

The widow of Alexander Litvinenko has welcomed a visit to Russia by the British Prime Minister David Cameron.

Mr Cameron is the first British Prime Minister to go to Russia since Mr Litvinenko - a critic of the Kremlin - was murdered in London in 2006.

The case caused a diplomatic row between Britain and Russia, as Moscow has refused to extradite the main suspect in the case, Andrei Lugovoi - a former KGB officer and now member of the Russian parliament. Mr Lugovoi denies any involvement.

Alexander Litvinenko's widow, Marina, told BBC World Service that she, and the rest of her family, are still waiting to see justice done.