Call me a skeptic, but this one sounds like a PR stunt by the book publisher. Today in the FT:
Russian exile cancels London visit after FBI security advice By Jimmy Burns A Russian exile who co-authored a book with Alexander Litvinenko, the murdered former KGB agent, has cancelled a visit to London after being advised by the Federal Bureau of Investigation his safety might be at risk, his publishers said -yesterday. Yuri Felshtinsky, an academic who lives in the US, was expected to attend the launch of the new edition of the book in London on Friday with a press conference and interviews. But Gibson Square Books, his UK publishers, said they had postponed the event indefinitely after receiving an e-mail from the author confirming the FBI advice. Martin Rynja, the publisher, said: “When the book was first written, everyone thought Litvinenko’s claims were ludicrous. Now people want to know what he stood for, which is why we are publishing it. It does seem now that if you are opposed to the KGB or its successors you are in trouble.” … Mr Felshtinsky’s visit was cancelled 24 hours after the widow of Mr Litvinenko appeared on a BBC Panorama programme and said no opponent of Mr Putin’s regime was safe. The claim was denied by the president’s spokesman.
There’s also coverage by Kommersant