( Sky news ) - A Moscow-based man is to be charged in connection with the murder of ex-Russian spy Alexander Litvinenko, if he can be extradited from Russia.
Crown Prosecution Service (CPS) has said it will ask for former KGB agent Andrei Lugovoi to be returned to the UK.
At a news conference Director of Public Prosecutions Sir Ken Macdonald said: "I have today concluded that the evidence given to us by the police is sufficient to charge Andrei Lugovoi with the murder of Mr Litvinenko by deliberate poisoning.
"I have instructed CPS lawyers to take immediate steps to seek the early extradition of Andrei Lugovoi from Russia to the United Kingdom, so that he may be charged with murder - and be brought swiftly before a court in London to be prosecuted for this extraordinarily grave crime."
But within minutes of the announcement the Russian state prosecutor said there was "no chance" of Mr Lugovoi being extradited.
Foreign Secretary Margaret Beckett said she had told Russia's ambassador she expects "full co-operation" over the extradition request.
But Sky News' foreign affairs editor Tim Marshall explained that the British Government was unlikely to force the issue.
"The CPS has been at pains to point out that this is a criminal, not a diplomatic case," he said.
"The Government doesn't want to make this about the UK versus Russia.
"I doubt we'll see a minister demanding the extradition of Mr Lugovoi."
Andrei LugovoyAlexander Litvinenko met Mr Lugovoi at the Millennium Hotel in Grosvenor Square in November last year, along with another Russian, Dmitry Kovtun.
Later that day, Mr Litvinenko complained of feeling ill and was admitted to hospital shortly afterwards.
He died three weeks later from polonium 210 poisoning.
The former KGB officer was a fierce critic of President Vladimir Putin's regime and had been granted political asylum in the UK.
On his death bed he accused the Russian President of being responsible for his death.
In a statement, he said: "You may succeed in silencing one man, but the howl of protest from around the world will reverberate, Mr Putin, in your ears for the rest of your life.
"May God forgive you for what you have done, not only to me, but to beloved Russia and its people."