The United States on Wednesday imposed sanctions on three entities it accused of being tied to arms deals between North Korea and Russia as Washington cracks down on those seeking to support Russia’s war in Ukraine.

The U.S. Treasury Department in a statement said that Russia has increasingly been forced to turn to North Korea and other allies to sustain its war in Ukraine as it expends munitions and loses heavy equipment on the battlefield.

The action is the latest by Washington, which has imposed rafts of sanctions targeting Moscow and Russian President Vladimir Putin since the start of the war, which has killed tens of thousands of people and turned cities to rubble.

“The United States continues to root out illicit financial networks that seek to channel support from North Korea to Russia’s war machine,” Treasury’s Under Secretary for Terrorism and Financial Intelligence Brian Nelson said in the statement.

“Alongside our allies and partners, we remain committed to exposing and disrupting the arms trade underpinning Putin’s brutal war in Ukraine.”

The entities targeted in Wednesday’s action are Limited Liability Company Verus, Defense Engineering Limited Liability Partnership and Versor S.R.O.