Mikhail Trepashkin, now serving a four-year sentence for divulging state secrets, has said in a letter that he warned Alexander Litvinenko, a former spy who died of radiation poisoning November 23, of a planned attempt on his life to avenge his defection in 2000.
Trepashkin said he wanted to give testimony to Scotland Yard investigators, due to arrive in Moscow Monday as part of an investigation into the high-profile case.
"He warned Litvinenko, among other things, of events that later materialized," Yelena Liptser told a news conference. "And now he is ready to give evidence to the British security services, and we believe his evidence should be heard."
The death of Litvinenko, 43, a fierce critic of the Kremlin, has stirred heated media debate and tarnished Russia's international image, as the former spy purportedly left a deathbed message implicating President Vladimir Putin in his poisoning.
Moscow has repeatedly denied the accusations, also casting doubt over the authenticity of the note. And Russian Foreign Minister Sergei Lavrov said Monday the scandal fanned by the media in the UK had damaged Russian-British relations.
Scotland Yard detectives are coming to interview several people who met with Litvinenko around the time of his alleged poisoning in early November, including businessman and former KGB and FSB colleague Andrei Lugovoi, and businessmen Dmitry Kovtun and Vyacheslav Sokolenko. The names of two other witnesses have not been disclosed.
The scandal rocked London as in ongoing investigations run by Scotland Yard trace amounts of radiation have been discovered at 12 sites in Britain and on two British Airways planes that flew the Moscow-London route. Dozens of people have since undergone medical tests for radiation.
Lev Ponomaryov, head of Russia's For Human Rights movement, said Monday that Trepashkin had warned of preparations being made for an attempt on Litvinenko and his family, adding that he had earlier handed over Trepashkin's letters to Scotland Yard.
Ponomaryov said an independent parliamentary commission should be set up to inquire into the assassinations of high-profile Kremlin opponents, including Litvinenko, investigative journalist Anna Politkovskaya October 7, and prominent lawmaker Galina Starovoitova in 1998.
"We also hope a commission will not be indifferent to Trepashkin's fate," he said.
Trepashkin was sentenced to prison in 2004 when a court found that while serving with the KGB, and later as an officer with its principal successor, the Federal Security Service, from 1984 to 1997, Trepashkin made copies of internal documents and stored them at home.