Russia's Justice Ministry says it has filed a lawsuit to shut down a company used by opposition leader Alexei Navalny that is being used to fund his political campaigning.

The Justice Ministry said Monday it has asked a Moscow court to close the Fifth Season of the Year foundation, which rents premises for Navalny's headquarters and employs campaign workers, over unspecified violations.

Navalny has unofficially campaigned for the presidency despite an implicit ban on his candidacy due to a fraud conviction seen by many as politically driven. Election officials last month formally barred him from the March 18 vote, which President Vladimir Putin is set to easily win.

Navalny has urged a boycott of the election, and tweeted Monday that the ministry's move reflects authorities' fear of the "voters' strike."