( AFP ) - Russia will try ex-KGB agent Andrei Lugovoi for the murder in London of fugitive Russian agent Alexander Litvinenko if Britain provides sufficient evidence of his guilt, news agencies quoted Prosecutor General Yury Chaika as saying Friday. British authorities said this week they would seek the extradition of Lugovoi, whom they formally charged with the poisoning murder of Litvinenko, though Russia has insisted it will not extradite him.
"I told British Attorney-General (Lord Peter) Goldsmith today that if the British side presents us with evidence of Lugovoi's guilt and we consider it sufficient, he may be brought to justice" in Russia, Chaika told Interfax by telephone from Munich, Germany.
Russia says its constitution forbids extraditing citizens to be tried abroad.
The firm stand has deepened a diplomatic crisis between the two states over the killing last year of Litvinenko, a former Russian security services officer and Kremlin critic who had political asylum in Britain.
The murder sent shockwaves through British society, where hundreds of people were tested for radiation exposure after investigators established that Litvinenko was poisoned with the rare radioactive isotope polonium-210.
Suspicion soon focused on Lugovoi, who met with Litvinenko in a London hotel on November 1, and later left a trail of polonium traces across Europe while travelling back to Russia.
Lugovoi -- a Soviet KGB officer who specialised in bodyguard duties and now owns a security company and soft drinks factory -- has angrily asserted his innocence.
The British government has demanded "full cooperation" from Moscow in bringing him to justice, and has discussed the case with Russia's ambassador in London.
Litvinenko died in agony on November 23 from the poisoning. A final letter distributed by friends accused President Vladimir Putin of ordering the assassination.