The U.K. will officially declare the Wagner Group as a terrorist organization, according to a on Sept. 6 statement from the British Home Office.
The Russian private military company will join al-Qaeda and ISIS on the list of proscribed terrorist organizations in the U.K.
After the order comes into effect on Sept. 13, it will be a criminal offense to be a member of Wagner, use its logo, or encourage support for the group.
"Wagner is a violent and destructive organization which has acted as a military tool of Vladimir Putin’s Russia overseas," said U.K. Home Secretary Suella Braverman .
"They are terrorists, plain and simple," Braverman added.
Designating the group a terrorist organization comes after calls from President Volodymyr Zelensky to treat the group as terrorists and "careful consideration of the nature and scale of the organization's activities," according to the U.K. home office.
The U.K. included the group in a wave of sanctions against Russia after the start of the full-scale invasion of Ukraine in February 2022.
In July 2023, it also sanctioned 13 individuals and businesses linked to Wagner's activities in Africa.
The British government said it believes the security threat posed by the Wagner Group will endure, "despite recent events."
The mercenary group's leader, Yevgeny Prigozhin, was killed in an Aug. 23 private jet crash.
While the reasons for the crash of Prigozhin's aircraft remain unclear, U.S. officials named a bomb onboard or "some other form of sabotage" as a likely cause of the incident. Russia rejected an offer by Brazil to assist with the investigation of the plane's crash.
The leader of the mercenary group launched a short-lived rebellion against the Kremlin in late June. He captured the city of Rostov and marched toward Moscow before abruptly ending the insurrection.
Following an undisclosed deal allegedly brokered by Belarusian dictator Alexander Lukashenko, the warlord was allowed to walk free and released a video claiming to be in Africa shortly before his death.
The Wagner Group became infamous in 2022 for bringing tens of thousands of convicts from Russia's prisons into its ranks to fight in Ukraine, including those convicted of rape and murder, and used them as a highly effective but expendable assault force.
Lithuania's parliament recognized the Wagner Group as a terrorist organization in March 2023.