[JURIST] A UK intelligence official said Tuesday that there are "very strong indications" that the Russian government was behind the murder of former KGB agent and British citizen Alexander Litvinenko [JURIST news archive; BBC timeline]. The official made the comments [BBC video clip] anonymously during a television interview with the BBC, and asserted that the type of poison used proves Russia's involvement in the plot. The UK has a strained relationship with Russia, due partly to Russia's refusal to extradite Andrei Lugovoy [JURIST news archive], the man suspected of actually administering the poison, so that he could stand trial for murder [JURIST report] in the UK. Russian officials say the Russian constitution prohibits the extradition of citizens for criminal trials in other countries [JURIST report]. While the government has offered to prosecute Lugovoi in Russia, it contends that the UK has not yet provided any credible evidence [JURIST report] to link Lugovoy to the murder. BBC News has more.

Litvinenko and Lugovoy, both former employees of the Federal Security Service of the Russian Federation (FSB) [official website], met in London on November 1, 2006, hours before Litvinenko fell ill to radioactive poisoning. UK Ambassador to Russia Sir Tony Brenton has implied [JURIST report] that the Russian constitution should not prevent Lugovoy's extradition, alleging that the Russian government routinely ignores its own laws. Former Russian President Vladimir Putin [official website; JURIST news archive] rebuked the comments, characterizing the UK's demand for the extradition as "a clear remnant of colonial thinking." The two countries have battled politically since Litvinenko's death, with each expelling a number of the other country's diplomats in July 2007 and Russia closing down local offices of the British Council in December 2007 [JURIST reports].