Thousands of protesters have rallied in cities across Russia in a last-ditch effort to secure the freedom of the hunger-striking opposition leader Alexei Navalny. The unauthorised demonstrations have shown the determination of Navalny's core supporters, who called for freedom for political prisoners!" in tense standoffs with riot police in helmets and body armour. It comes on the same day Vladimir Putin delivered a tough message to western nations in his state of the nation address. Moscow correspondent Julia Chapman spoke to Corin Dann.