Russian billionaire Alisher Usmanov has published a video tirade against opposition leader Alexei Navalny, branding him a “loser” in a 12-minute online rant.

Usmanov, who is currently suing Navalny for libel, labeled the presidential hopeful a “criminal,” unable to grasp basic business concepts.

The businessman published the clip on Wednesday evening, the day before case appeared in court.

"[Navalny is] just an ignoramus. In the last ten years, my businesses have created 40,000 jobs and invested more than 800 billion rubles in technology, in infrastructure," Usmanov said.

"Unlike [Navalny], I have achieved everything using hard work, ability, and honesty: you can never slander me in life."

Usmanov took Navalny to court after the politician accused him of paying bribes to Russian Prime Minister Dmitry Medvedev.

Navalny's Anti-Corruption Foundation (ACF) publicly alleged that Usmanov had given Medvedev a plot of land with property worth 5 billion rubles ($87.8 million) in the Russian village of Znamenskoe under the guise of a donation to the Sotsgosproekt Foundation, a charity associated with Medvedev’s former classmate Ilya Yeliseyev.

The billionaire has denied the claims, saying instead that he had donated the mansion in exchange for real estate the organization already owned near Usmanov’s home.

Russian Billionaire Posts 'Loser' Rant Against Opposition's Navalny