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MOSCOW, May 30 (RIA Novosti) - Russia insists on the extradition of Boris Berezovsky from the United Kingdom, but will not swap a suspect in a poisoning case for him, a Prosecutor General's Office spokesman said Wednesday.

Britain officially requested Monday the extradition of Andrei Lugovoi, suspected of murdering ex-FSB officer Alexander Litvinenko in London last November. Although an exchange for Berezovsky has not been raised officially, a senior Russian lawmaker said a few days ago this "could be a subject for talks."

"The legislator's proposal is his personal opinion, and does not reflect the official position of the Russian authorities," the spokesman said. "The Prosecutor General's Office is not even considering this issue, because such an action is impossible from the viewpoint of Russian laws, primarily the Constitution, which states that a Russian national cannot be extradited to another state."

The Russian Prosecutor General has repeatedly stated that such an exchange would be impossible under international law, and made the point at his meeting with U.K. Attorney General Lord Peter Goldsmith in Munich last week.

Litvinenko, a former Federal Security Service officer who received British citizenship a few weeks before his fatal poisoning on November 1 last year, accused Russia's president of orchestrating his death, a charge that Vladimir Putin dismissed as ridiculous. The case, investigated both in London and Moscow, has strained relations between the countries.

Berezovsky, a billionaire who emigrated to the United Kingdom in 2001 and was granted political asylum, is wanted in Russia on charges of fraud and corruption. In January this year, he caused an international stir by announcing in media interviews that he was working on overthrowing Putin's administration by force. All Russia's requests for Berezovsky extradition have so far been declined since 2002.

The prosecutors' spokesman said: "As far as Berezovsky is concerned, our requests for his extradition are legitimate, we are complying with international norms and we believe our requests will be met in the long run."