London: An inquiry into the radiation poisoning of a former Russian spy opened Tuesday with claims that there may have been an earlier assassination bid in the most sensational tale of espionage since the Cold War.
Alexander Litvinenko was killed -- apparently via a cup of green tea laced with hard-to-detect polonium-210 -- in an upmarket London hotel in 2006.
The inquiry will look into claims of Russian state involvement and on Tuesday it heard chilling extracts from Litvinenko`s interviews with police conducted at his hospital deathbed.
Russia has refused to extradited the two men identified by British police as the chief suspects -- Andrei Lugovoi and Dmitri Kovtun -- who drank tea with Litvinenko on November 1, 2006.
Counsel to the inquiry Robin Tam said Tuesday that traces of polonium found from a previous meeting between the three on October 16 in the offices of a London security firm may indicate a previous poisoning attempt.
"One of the most significant things that the evidence suggests is that Litvinenko was poisoned with polonium not once but twice," he said.
Tam also revealed that a friend of Kovtun from Germany will testify that the Russian told him he had poison and needed a contact for a cook to kill Litvinenko.
"Kovtun said that he had a very expensive poison and that he needed the cook to put the poison in Litvinenko`s food or drink," Tam said.
Litvinenko, who was doing work for Britain`s MI6 foreign intelligence service, died on November 23, 2006 -- three weeks after the poisoning.
A deathbed statement in his name accused President Vladimir Putin directly, saying that "the howl of protest from around the world will reverberate, Mr Putin, in your ears for the rest of your life".
The inquiry`s chairman Robert Owen said at the start of Tuesday`s hearing that closed-doors hearings would examine intelligence material on "the issue of Russian state responsibility".
The hearings are due to last two months and Owen said his report would be out by the end of the year. Britain`s Daily Telegraph newspaper reported at the weekend that communications between London and Moscow intercepted by the US National Security Agency pointed to Russian state involvement.
At the time, Putin rejected the accusations as a "political provocation".
There are other theories about who may have killed him, given Litvinenko`s investigative work in other European countries including Italy and Spain and his specialisation in researching organised crime.
Owen was the coroner in a previous inquest into the death but did not have the power to examine intelligence documents. He lobbied for an inquiry to be able to do so.
Under English law, such inquiries establish the facts of a case in public but do not result in convictions.Britain announced the inquiry in July 2014, just days after the downing of a Malaysian passenger jet over eastern Ukraine -- a tragedy blamed on Russia`s involvement in the conflict in the region -- in what was seen as a way of punishing Moscow.
The spy`s wife Marina Litvinenko told AFP the inquiry was the best she could hope for.
"My struggle has been for the facts to be made public," she said, adding: "This is the last thing I can do for him, defend his name.
Litvinenko served in the KGB during Soviet times and then in its successor agency, the FSB.
In 1998, he and other FSB agents gave a press conference in Moscow accusing the agency of a plot to kill Boris Berezovsky, an oligarch who helped bring Putin to power but later turned against him.
Litvinenko was tried for abuse of power and although acquitted in 1999 he fled Russia, apparently through Georgia and Turkey with a fake passport.
He was later tried and sentenced in absentia on different charges that his family says, like the abuse of power allegations, were invented to silence him.
Litvinenko was granted asylum in Britain and later became a British citizen.
A veteran of the 1994-1996 Chechen war, he later converted to Islam after befriending exiled Chechen separatist leaders.
He was buried in a London cemetery with Muslim rites in lead-lined coffin to prevent radiation leakage.