Updated

A Russian court has sentenced a close ally of opposition leader Alexei Navalny to a month in jail for organizing an unauthorized rally.

The district court in the city of Nizhny Novgorod on Friday found Leonid Volkov guilty of breaking the law on public gatherings. Volkov is the chief of Navalny's presidential campaign.

Navalny plans to run for president against Vladimir Putin in the March election. Navalny and his allies have repeatedly served jail terms connected to rallies critical of the Russian government. Navalny himself spent 20 days in jail in October for organizing another rally.

Demonstrations called for by Navalny this year were some of the largest in years, rattling the Kremlin.

Navalny tweeted on Friday that Volkov's jailing aims to "paralyze" his campaign.