Russia's Supreme Court on Wednesday canceled the conviction of prominent anti-Kremlin activist Ildar Dadin and ordered his release from jail, Interfax news agency reported.

Dadin, 34, was sentenced to three years in prison - reduced to two and a half on appeal - in December 2015 for a series of peaceful one-man protests against the Kremlin.

"Dadin is to be released from custody," Interfax cited the ruling as saying.

The motion came after the Constitutional Court on Feb 10 ordered a review of Dadin's conviction, arguing that a law that criminalized certain types of protests had to be applied more proportionately.

Dadin was the first person to be jailed under a 2014 law, adopted after big anti-Kremlin protests, that criminalized the violation of protest rules more than twice in 180 days.

Last November, Dadin said he was tortured in jail in northwest Russia. Jail officials dismissed the allegations, but the activist was subsequently moved to another prison.