Joe Biden has paid tribute to Alexei Navalny following his death, saying his courage will “not be forgotten”.
Russia’s federal prison service said in a statement that Navalny, the 47-year-old opposition politician regarded as Vladimir Putin’s fiercest critic, had died on Friday 16 February.
According to the agency, he became unwell after a walk and lost consciousness.
“God bless Alexei Navalny, his courage will not be forgotten, and I’m sure it will not be the only courage we see coming out of Russia,” Mr Biden said.