Russian opposition leader Alexei Navalny has been freed from prison after serving a 20-day sentence for organising a rally without official permission from authorities.
He was taken into custody late last month as he prepared to travel to Nizhny Novgorod, Russia's fifth-biggest city, to lead a rally.
He was arrested for organising another rally in St Petersburg, President Vladimir Putin's hometown, without authorisation, although the rally in Nizhny Novgorod had the proper permits.
After he was released from jail on Sunday, the opposition leader posted on social media that he planned to participate in an evening anti-government protest in the city of Astrakhan.
Navalny, 40, a staunch Kremlin critic and anti-corruption campaigner, has long been the most visible opposition figure to Putin's rule. He plans to run for the presidency against Putin in the March election.
Navalny rose to prominence in Russian politics in 2008, when he started blogging about alleged corruption at some of Russia's large, state-controlled corporations.
Navalny used social media to reach out to predominantly young followers, mocking the establishment loyal to Putin. He rallied tens of thousands of people during widespread anti-Putin protests across the country.
He came second in the 2013 Moscow mayoral race after a grassroots campaign against the Kremlin-backed candidate. Navalny launched hundreds of lawsuits contesting the victory of his rival, Sergei Sobyanin.
Navalny has been in jail multiple times in relation to anti-government protests.
