The UK has announced it will be sanctioning the Wagner Group, BBC reported.
The organisation is a group of mercenaries that was first identified in 2014 when it was backing pro-Russian separatists in the conflict in eastern Ukraine.
Since then, it has been involved in other regions too, including Syria, Mozambique, Sudan, and the Central Asian Republic. The paramilitary group has been described as Vladimir Putin's private army.
It's been warned that the group has been tasked with assassinating Ukrainian President Volodymyr Zelensky, BBC reported.
UK Foreign Secretary Liz Truss described the group as "hired thugs" in her statement on the new sanctions - saying they, alongside oligarchs and businesses, are "complicit in the murder of innocent civilians and it is right they pay the price".
Officially there are no ties between the Wagner Group and the Russian government - it denies any state involvement with the group, while also maintaining it does not legally exist because private military contractors are illegal in Russia, BBC reported.
It is believed to be funded by Yevgeny Prigozhin, a rich businessman with links to Putin. But Prigozhin has always denied any connection with Wagner.
Announcing the new sanctions UK Foreign Secretary Liz Truss said: "Putin should be under no illusions – we are united with our allies and will keep tightening the screw on the Russian economy to help ensure he fails in Ukraine. There will be no let-up."