White House National Security Council spokesman John Kirby said U.S. intelligence officials determined that North Korea completed an initial arms shipment that included rockets and missiles last month.
"We assess that the amount of material delivered to Wagner will not change battlefield dynamics in Ukraine," Kirby said. "But we’re certainly concerned that North Korea is planning to deliver more military equipment."
The White House has expressed alarm about Wagner's growing presence in the Ukraine war, with the mercenaries particularly active in the eastern Donbas region. Kirby said in certain instances Russian military officials have even been "subordinate to Wagner's command."
Kirby said the U.S. now assesses that Wagner has some 50,000 personnel fighting in Ukraine, including 10,000 contractors and 40,000 convicts that the company has recruited from prisons.
The U.S. assesses that Wagner, owned by Putin ally Yevgeny Prigozhin, is spending about $100 million a month in the fight, Kirby said.
Wagner has faced U.S. sanctions since 2017. The Commerce Department on Wednesday unveiled new export restrictions targeting Wagner in a bid to further restrict its access to technology and supplies.
The White House has repeatedly sought to spotlight intelligence findings that show Russia — struggling to maintain a steady supply of arms for its war in Ukraine and pinched by sanctions — has limited options to help it resupply weapons.
Russia has also turned to Iran to provide drones to use against Ukraine. The Biden administration has expressed concern that Russia may seek to acquire additional advanced conventional weapons from Iran. The White House has previously said that Moscow was looking to North Korea to provide it with artillery.
Wagner Group mercenaries have been accused by Western countries and U.N. experts of numerous human rights abuses throughout Africa, including in the Central African Republic, Libya and Mali.
Earlier this month, Secretary of State Antony Blinken announced he had designated the Wagner Group as an "entity of particular concern" for its activities in the Central African Republic.