British prosecutors say they have sufficient evidence to press murder charges in last year's death by radiation poisoning of former Russian spy Alexander Litvinenko.
Britain's Crown Prosecution Service said Tuesday it has instructed its lawyers to seek the extradition from Russia of Andrei Lugovoi, a former officer with the Russian intelligence service. The CPS called Litvinenko's killing an extraordinarily grave crime and its prosecution "clearly in the public interest".
Litvinenko had also been in Russian intelligence, but became a critic of the government and fled to Britain, where he acquired citizenship. On his deathbed, he accused Russian President Vladimir Putin of his murder.
The case has strained ties between Britain and Russia, which earlier said it would not extradite any suspects for trial in Britain.
Some information for this report was provided by AFP and AP.