The US Treasury Department said in a statement that Russia was continuing to use up munitions and lose heavy equipment in Ukraine, forcing it to turn to its small pool of allies, including North Korea, for support.

The department said it had "imposed sanctions on three entities tied to a sanctions evasion network attempting to support arms deals between Russia and the Democratic People's Republic of Korea" (DPRK).

"This action is part of the continuing U.S. strategy to identify, expose, and disrupt third-country actors seeking to support Russia's brutal war against Ukraine," it added.

The entities targeted are Limited Liability Company Verus, Defense Engineering Limited Liability Partnership and Versor S.R.O.

"The United States continues to root out illicit financial networks that seek to channel support from North Korea to Russia's war machine," Brian Nelson, the Treasury's under secretary for terrorism and financial intelligence, said in the statement.

"Alongside our allies and partners, we remain committed to exposing and disrupting the arms trade underpinning (Russian President Vladimir) Putin's brutal war in Ukraine."

The department said all three entities were linked to Slovakian national Ashot Mkrtychev, who was himself sanctioned in March.

"Through his negotiations with DPRK and Russian officials, he organized potential plans to transfer over two dozen kinds of weapons and munitions to Russia in exchange for a range of goods, including raw materials and commodities, to the DPRK," the department said.

The sanctions will block all properties and interests linked to the three entities that come under US jurisdiction.