Robert Owen, a retired judge serving as the inquiry's chairman Thursday announced his year-long inquiry had confirmed the Russian state was responsible for the November 2006 poisoning of Litvinenko, carried out by two Russian agents at the Millennium Hotel in central London just a few meters from the U.S. Embassy.

But Putin spokesman Dmitry Peskov told reporters Thursday that "such a quasi-investigation such as the one being talked about today undoubtedly is able only to still further poison the atmosphere of our bilateral relations".

"The accusations brought against me are absurd", he said. She described it as a "blatant and unacceptable breach of worldwide law and civilized behavior".

— The judge notes that although he can not be sure that the poison that killed Litvinenko came from Russian Federation, it is clear that it had been manufactured in a nuclear reactor, suggesting that the suspects "were acting for a state body, rather than (say) a criminal organization". President Vladimir Putin probably approved a plan by Russia's FSB security service to kill former agent Alexander Litvinenko, a British judge said Thursday. On Thursday, the Russian Foreign Ministry dismissed the British inquiry process as biased and opaque.

High polonium contamination was found in the teapot and the hotel bar.

"The results of the investigation made public today yet again confirm London's anti-Russian position, its blinkeredness and the unwillingness of the English to establish the true reason of Litvinenko's death".

As a lawmaker, he is now immune from prosecution in Russian Federation.

— He concludes that there is a "strong probability" that Lugovoi and Kovtun poisoned Litvinenko under the direction of Russia's FSB spy agency.

The chair of the independent inquiry was certain Mr Litvinenko was given tea laced with a fatal dose of radioactive polonium-210 at a London hotel.

Vladimir Putin "probably" approved the killing of a former Russian spy in London 10 years ago.

"I am satisfied that in general terms, members of the Putin administration, including the president himself and the FSB, had motives for taking action against Litvinenko, including killing him, in late 2006", Sir Robert wrote.

Moscow has always denied having anything to do with murdering Litvinenko, who "had repeatedly targeted President Putin" with "highly personal" public attacks and accusing him of corruption. He fled to Britain in 2000 before he was granted asylum in 2001 and became a British citizen in October 2006.

British police have accused Dmitry Kovtun and Andrei Lugovoi of carrying out the killing, sponsored by elements in the Kremlin.

Litvinenko, 43, was an outspoken critic of Mr Putin.

- Interpol has issued notices calling for their arrest, although Russian Federation refuses to extradite them.

The Russian ambassador in London was summoned to the foreign office so the British government could express what it called its profound displeasure at Russia's failure to cooperate in the case.