British prosecutors on Tuesday requested the extradition of former KGB agent Andrei Lugovoi to face a charge of murder in the poisoning death of former operative Alexander Litvinenko, officials said Tuesday.

Lugovoi met Litvinenko at a London hotel only hours before Litvinenko became ill with polonium-210 poisoning. He has repeatedly denied any involvement in the case during interviews with the police and media.

The Interfax news agency on Tuesday cited the Russian prosecutor-general's office as saying it will not turn over Lugovoi to British authorities.

"Murder is murder, this is a very serious case," Blair's spokesman said while speaking on condition of anonymity in line with government policy. "The manner of the murder was also very serious because of the risks to public health."

Litvinenko, 43, died Nov. 23 after ingesting the rare radioactive isotope. On his deathbed, he accused President Vladimir Putin of being behind his killing. The Russian government denies involvement.