SEOUL/WASHINGTON -- The White House said North Korea has delivered an arms shipment to a private Russian military company, the Wagner Group, for use in the Ukraine war.

John Kirby, the National Security Council spokesperson, told reporters Thursday (US time) that North Korea completed an initial shipment of weapons to Russia, including infantry rockets and missiles last month.

"We can confirm that North Korea has completed an initial arms delivery to Wagner, which paid for that equipment," he said.

North Korea has flatly denied allegations that it has had arms transactions with Russia. Wagner owner Yevgeny Prigozhin reportedly dismissed the assertion as "gossip and speculation."

North Korea's foreign ministry on Friday issued another statement denying relevant suspicions in response to a Japanese media report that the North has transported munitions to Russia by rail.

The Tokyo Shimbun reported the previous day that the North transported artillery shells and other munitions via train linking the North's northeastern border city of Rason with Khasan in neighboring Russia.

"The Japanese media's false report that the DPRK offered munitions to Russia is the most absurd red herring, which is not worth any comment or interpretation," an unnamed spokesperson at the North's foreign ministry said in the English-language statement carried by the Korean Central News Agency.

DPRK is the acronym for North Korea's official name, the Democratic People's Republic of Korea.

North Korea's arms exports are banned under UN Security Council resolutions against Pyongyang's nuclear and missile programs. (Yonhap)