President Putin critic describes how it felt to be poisoned

A prominent critic of President Putin has accused the Russian secret services of poisoning him for a second time in two years.

Vladimir Kara-Murza, who runs the Open Russia Movement, told Radio 4's Today how he fell into a coma after suddenly becoming unwell when he was in Moscow in February.

The official diagnosis in his hospital notes was "toxic action by an unidentified substance" which he says "translates from medical language into ordinary language as poisoning".