LONDON, Sept 21 (Reuters) - The European Court of Human Rights found on Tuesday that Russia was responsible for the assassination of ex-KGB officer Alexander Litvinenko, who died an agonising death in 2006 after being poisoned in London with a rare radioactive substance.
Litvinenko, a defector who had become a vocal critic of the Kremlin, died three weeks after drinking green tea laced with polonium-210 at a plush London hotel.
Britain has long blamed the attack on Moscow, and the European court in Strasbourg, France, agreed on Tuesday, saying in a statement that "Mr Litvinenko’s assassination was imputable to Russia", prompting a swift rebuke from the Kremlin.
The image of Litvinenko, 43, lying on his bed at London’s University College Hospital, yellow, gaunt and with hair fallen out, was emblazoned across British and other Western newspapers.
From his deathbed, Litvinenko told detectives he believed President Vladimir Putin - himself a former KGB spy - had directly ordered his killing, a charge the Kremlin denied.
The use of a rare radioactive isotope on the streets of London, apparently to settle scores, plunged Anglo-Russian relations and Western mistrust of the Kremlin to what was then a post-Cold War low.
A British inquiry concluded in 2016 that former KGB bodyguard Andrei Lugovoy and another Russian, Dmitry Kovtun, carried out the killing as part of an operation probably directed by the Federal Security Service (FSB), the main successor to the Soviet-era KGB.
Endorsing that view, the ECHR said it had found "beyond reasonable doubt that the assassination had been carried out by Mr Lugovoy and Mr Kovtun".
"The planned and complex operation involving the procurement of a rare deadly poison, the travel arrangements for the pair, and repeated and sustained attempts to administer the poison indicated that Mr Litvinenko had been the target of the operation."
'EXTREMELY IDIOTIC'
Kremlin spokesman Dmitry Peskov rejected the accusation.
"The ECHR hardly has the authority or technological capacity to possess information on the matter," he said. "There are still no results from this investigation and making such claims is at the very least unsubstantiated."
Lugovoy and Kovtun have always denied involvement. On Tuesday Lugovoy said the ECHR ruling was politically motivated.
"I think it is extremely idiotic and damaging to the reputation of the European Court of Human Rights," Lugovoy, a member of Russia's parliament, told Reuters.
In a separate development on Tuesday, British police said a third Russian had been charged in absentia with the 2018 Novichok murder attempt on former double agent Sergei Skripal, saying they could also now confirm the three suspects were military intelligence operatives.
Russia has also rejected any involvement in that case, which led to tit-for-tat expulsion of dozens of diplomats.
In the 2006 incident, polonium contamination was found in the teapot and the hotel bar where Litvinenko had been, and traces of the highly radioactive substance were left across London - in offices, hotels, planes and Arsenal soccer club’s Emirates Stadium.
But with the main suspects out of reach in Russia, Britain was unable to pursue criminal proceedings.
Litvinenko's widow Marina took the case to the ECHR, arguing that her husband had been killed "on the direction or with the acquiescence or connivance of the Russian authorities and that the Russian authorities failed to conduct an effective domestic investigation into the murder".
NOT 'ROGUE OPERATION'
In finding the Russian state responsible for Litvinenko's death, the ECHR said Moscow would have had the information to prove it if the men been carrying out a "rogue operation".
"However, the government had made no serious attempt to provide such information or to counter the findings of the UK authorities," it said.
A Russian judge sitting on the ECHR panel, Dmitry Dedov, disagreed with his six colleagues on the court's main finding.
"I found many deficiencies in the analysis by the British inquiry and by the Court which raise reasonable doubts as to the involvement of the suspects in the poisoning and whether they were acting as agents of the State," he said.
The ECHR ordered Russia to pay Marina Litvinenko 100,000 euros ($117,000) in damages and 22,500 euros in costs.
The judge who oversaw the British inquiry said there were several reasons why the Russian state would have wanted to kill Litvinenko, who was granted British citizenship a month before his death on Nov. 23, 2006.
The ex-spy was regarded as having betrayed the FSB by accusing it of carrying out apartment block bombings in Russia in 1999 that killed more than 200 people, which the Kremlin blamed on Chechen rebels.
He was also close to other leading Russian dissidents and had accused Putin's administration of collusion with organised crime. The judge said the FSB also had information that he had started working for Britain’s foreign intelligence agency, MI6.
