Russian tycoon Alisher Usmanov has filed a defamation lawsuit against opposition leader Aleksei Navalny.
The Lyublino district court in Moscow said on April 13 that Uzbek-born billionaire Usmanov named Navalny and his corruption-fighting organization in a suit aimed "to protect his honor and dignity."
The lawsuit stems from a March 2 report by Navalny's Anticorruption Foundation that focused on Prime Minister Dmitry Medvedev and included allegations that Usmanov gave expensive property to a foundation linked to Medvedev at no cost.
Usmanov has denied any wrongdoing.
The allegations against Medvedev helped galvanize nationwide anticorruption protests orchestrated by Navalny on March 26.
Navalny, who was jailed for 15 days over the protests, is calling for fresh anticorruption demonstrations on June 12.
He wants to run in a March 2018 election in which President Vladimir Putin is widely expected to seek and secure a new six-year term.