The U.K. government said that Russian mercenary company Wagner Group is being used by Russia to try to assassinate Ukrainian President Volodymyr Zelensky.

The group of hired soldiers was “reportedly tasked” with killing Mr. Zelensky, the U.K. government said, as it announced sanctions against Wagner Group. It didn’t provide evidence or further details.

Wagner emerged from Russia’s covert interventions in eastern Ukraine in 2014, where the Kremlin worked with armed groups funded by politically connected Russian businessmen. Wagner was financed in part by multimillion-dollar catering and construction contracts for the Russian armed forces awarded to companies linked with Yevgeny Prigozhin, a former restaurateur, according to European officials.

A representative of Mr. Prigozhin called into question the existence of Wagner Group and said questions about the U.K.’s claim represented “a severe psychosis of Western media,” without commenting on the claim itself. The company couldn’t be reached for comment.