While MI5 kept its focus on terrorism, Russian intelligence spotted an opening

Russian President Vladimir Putin "probably approved" the murder of Litvinenko, according to the British enquiry Photo:Reuters

David Blair
© Telegraph Media Group Limited

The public inquiry into the fate of Alexander Litvinenko lifted the veil on a particularly sordid Russian intelligence operation. We know that his murder was "directed" by the FSB and "probably approved" by Vladimir Putin himself. But how great is the espionage threat from Russia?

The Cold War is supposedly over, but Litvinenko's death provides vivid evidence of how the FSB and the SVR - the twin successors of the old KGB - continue to treat some countries such as Britain as priority targets.