Rishi Sunak has paid tribute to the "fiercest advocate for Russian democracy" after the country's prison agency said jailed opposition leader Alexei Navalny has died.The UK Prime Minister said Mr Navalny, a prominent and persistent critic of Vladimir Putin, had "demonstrated incredible courage throughout his life".Moscow's federal prison service said in a statement that Mr Navalny, 47, felt unwell after a walk on Friday and lost consciousness.An ambulance arrived to try to rehabilitate him, but

Rishi Sunak has paid tribute to the "fiercest advocate for Russian democracy" after the country's prison agency said jailed opposition leader Alexei Navalny has died.The UK Prime Minister said Mr Navalny, a prominent and persistent critic of Vladimir Putin, had "demonstrated incredible courage throughout his life".Moscow's federal prison service said in a statement that Mr Navalny, 47, felt unwell after a walk on Friday and lost consciousness.An ambulance arrived to try to rehabilitate him, but he died, the service said.There was no immediate confirmation of Mr Navalny's death from his team.