The United States has updated its sanctions on the Russian private military company Wagner Group and designated it as a "significant transnational criminal organization."

The US Treasury Department revised the sanctions on Thursday, saying they will also be imposed on eight individuals, 16 entities and four aircraft that support Russia's military operations.

The measures include asset freezes in the US and bans on business transactions with American individuals and companies.

Last Friday, White House National Security Council Coordinator for Strategic Communications John Kirby accused the Wagner Group of sending 50,000 fighters to Ukraine, including about 40,000 convicts recruited from Russia.

He said Moscow is increasingly dependent on the military company to continue fighting in Ukraine.