On 21 January 2016 a UK public inquiry concluded that the killing of Aleksandr Litvinenko, a former FSB officer, in 2006 in London was 'probably' approved by President Vladimir Putin. The BBC said that, according to the inquiry, ‘Mr Putin is likely to have signed off the poisoning of Mr Litvinenko with polonium-210 in part due to personal "antagonism" between the pair.’ The UK’s Home Secretary, Theresa May, said after the announcement of the conclusions of the inquiry that the murder was a 'blatant and unacceptable' breach of international law. The BBC quoted the Russian Foreign Ministry as saying the public inquiry was ‘politicised.’

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