The director of public prosecutions has recommended that a former KGB officer should be charged with the murder of ex-spy Alexander Litvinenko.
Sir Ken Macdonald has described the prosecution of Andrei Lugovoi as being "clearly in the public interest".
Here is Sir Ken's statement in full:
"On 23 November 2006 Mr Litvinenko died in a London hospital of acute radiation injury.
"He was found to have ingested a lethal dose of Polonium 210, a highly radioactive material.
"During his difficult, fatal illness and following his death, the Metropolitan Police Service in London conducted a careful investigation into how this had happened.
"Among the people of interest to police in this inquiry was a Russian citizen named Andrei Lugovoi.
"In late January 2007 the police sent a file of evidence to the Crown Prosecution Service so that we could make a decision about whether criminal charges should be brought against anyone who might have been involved in these events.
"Prosecutors from CPS Counter Terrorism Division have carefully considered the material contained in that police file.
"They have also asked the police to carry out further inquiries, which are now complete.
"And, finally, they have consulted with me.
"I have today concluded that the evidence sent to us by the police is sufficient to charge Andrei Lugovoi with the murder of Mr Litvinenko by deliberate poisoning.
"I have further concluded that a prosecution of this case would clearly be in the public interest.
"In those circumstances, 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."