An appeals court in Moscow has upheld a 15-day sentence for prominent Russian opposition leader Alexei Navalny.

The Moscow City Court ruled Friday that the Feb. 20 verdict by a district court, which sentenced Navalny to 15 days in custody, should stand. The court then found Navalny guilty of violating the law when he campaigned on the subway for an unauthorized "anti-crisis" march on March 1.

Navalny denied the accusations of breaking the law and argued they were intended to prevent him from organizing the demonstration amid a severe economic downturn in Russia caused by low oil prices and Western sanctions.

Navalny, the driving force behind the massive 2011-2012 anti-Putin protests in Moscow, has campaigned to organize anti-government protests in several Russian cities in March.