Russia recently fired North Korean ballistic missiles into Ukraine and is now seeking to acquire close-range ballistic missiles from Iran, a White House official said Thursday, as Moscow races to replenish its depleted stock of weapons.

White House national security spokesman John Kirby said North Korea has provided Russia with ballistic missile launchers, and the United States expects additional missiles supplied by Pyongyang will be used to target Ukraine's civilian infrastructure and kill its innocent people.

Citing intelligence but without elaborating further, he said the Russian military launched at least one of those ballistic missiles into Ukraine on Saturday, and that it landed in an open field in the Zaporizhzhia region.

White House national security spokesman John Kirby speaks at a press conference at the White House in Washington on Jan. 4, 2024. (AP/Kyodo)

He said multiple North Korean ballistic missiles with a range of about 900 kilometers were then fired on Tuesday from Russia as part of its overnight aerial attack, adding that the United States is still evaluating the impact.

"This is a significant and concerning escalation in (North Korea's) support for Russia," he said at a press briefing.

The United States had disclosed North Korea's delivery of military equipment and munitions to Russia for its aggression in Ukraine. But this is the first time U.S. officials have spoken publicly about Russia's use of North Korean missiles in the war that began in February 2022.

"Now, in return for its support, we assess that Pyongyang is seeking military assistance from Russia including fighter aircraft, surface-to-air missiles, armored vehicles, ballistic missile production equipment or materials and other advanced technologies," Kirby said.

He warned that their deepening relations have serious security implications for the Korean Peninsula and the Indo-Pacific region.

In October, the White House said North Korea delivered more than 1,000 containers of military equipment and munitions to Russia for its war in Ukraine.

The development followed North Korean leader Kim Jong Un's visit to Russia in September, during which he vowed support for Russian President Vladimir Putin.

Kirby also said the United States has assessed that Russia intends to purchase missile systems from Iran.

"The United States is concerned that Russia negotiations to acquire close-range ballistic missiles from Iran are actively advancing," he said.

As Russia has been intensifying its missile and drone attacks on Ukraine during the winter, he said the United States will raise those arms deals at the U.N. Security Council with its allies and partners, and impose additional sanctions on entities and individuals working to facilitate such transfers between Moscow and Pyongyang or Iran.

To prevent other countries from secretly aiding Russia's war machine, he said the United States will continue to release necessary information to the public, but stressed that the most effective response to the war is to provide Ukraine with essential air defense capabilities and other types of military equipment.

Extra aid for Ukraine is indispensable for that reason, he said, urging the U.S. Congress to approve the supplemental budget request sent by President Joe Biden in October, which has been blocked by Republicans.

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