North Korean troops are in Russia, Austin confirms.

Defense Secretary Lloyd Austin said Wednesday there is evidence North Korean troops are in Russia, branding their presence a “very serious” escalation in the war that started with Russia’s unprovoked invasion in 2022 and has left tens of thousands dead.

“There is evidence that there are DPRK troops in Russia,” Austin told reporters traveling with him in Rome, using North Korea’s formal name – the Democratic People’s Republic of Korea.

“What exactly they are doing? Left to be seen. These are things that we need to sort out,” Austin added.

A U.S. official confirmed Austin’s brief statement about North Korean troops in Russia. North Korea already has supplied Russia with large stores of artillery shells, a key component of the grinding fighting, especially in eastern Ukraine.

“It’s a big deal,” said Seth Jones, senior vice president and director of the international security program at the Center for Strategic and International Studies. “It is indicative of a conflict in Ukraine that is pulling in many of the world’s major powers into one battlefield.”

Russia is receiving aid from Iran and China as well as North Korea. Ukraine, Jones said, is facing “an axis of aggressors.”

He called for the Biden administration to loosen restrictions placed on U.S. weapons to allow Ukraine to target military facilities deep inside Russia.

Ukrainian President Volodymyr Zelenskyy has cited intelligence about the preparation of two units with possibly up to 12,000 North Korean troops who would take part in the war alongside Russian forces.

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Earlier Wednesday, South Korean lawmakers said North Korea has sent 3,000 troops to Russia to support its war against Ukraine, , following a briefing by the national intelligence agency. That estimate that is twice the previous figure cited by Seoul officials.

Pyongyang had promised to provide a total of about 10,000 troops, whose deployment was expected to be completed by December, the lawmakers told journalists.

A few thousand North Korean troops are unlikely to make much difference on the battlefield, said Michael O’Hanlon, a senior fellow at the Brookings Institution

“The key question for me is, will this expand into tens of thousands of troops?” O’Hanlon said. “That really could matter − and would also raise questions about what Russia was transferring to North Korea by way of technology to compensate for such a significant North Korean assistance.  But it remains to be seen if this will expand.”

The latest numbers came after Seoul’s National Intelligence Service said on Friday the North had sent some 1,500 special forces to Russia by ship.

More: North Korean shock troops in Ukraine? South Korea summons Russian ambassador over reports.

“Signs of troops being trained inside North Korea were detected in September and October,” Park Sun-won, a member of a parliamentary intelligence committee, said after the briefing.

“It appears that the troops have now been dispersed to multiple training facilities in Russia and are adapting to the local environment.”

Zelenskyy called on allies on Tuesday to respond to evidence of North Korean involvement in Russia’s war.

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Both Moscow and Pyongyang have denied arms transfers but have pledged to boost military ties, signing a mutual defence treaty at a summit in June. The Kremlin has dismissed as “fake news” South Korea’s claim about the North’s troop dispatch.

On Monday, a top U.S. diplomat said Washington was consulting with allies on the implications of North Korean involvement, adding that such a development would be a “dangerous and highly concerning development” if true.

Pyongyang has not publicly responded to the claims by Seoul and Kyiv, but authorities there made efforts to keep news of the dispatch from spreading, said Lee Seong-kweun, another lawmaker on the parliamentary committee.

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“There was even talk that the families of the selected soldiers cried so much that their faces were badly hurt,” Lee said, citing the spy agency.

“There are also signs of North Korean authorities relocating and isolating those families in a certain place in order to effectively control them and thoroughly crack down on the rumours.”

Lee also said the agency confirmed that Russia had recruited a “large number” of interpreters for the North Korean soldiers, while training them in use of military equipment, such as drones.

“Russian instructors are assessing that the North Korean military has excellent physical attributes and morale but lacks understanding of modern warfare such as drone attacks,” the lawmaker added.

“Therefore there could be many casualties if they are deployed to the front lines.”

On Tuesday the South’s presidential office urged an immediate withdrawal of the North’s troops from Russia, warning that it may consider supplying lethal weapons to Ukraine if military ties between them went too far.

Contributing: Reuters