US President Joe Biden said the development was “very dangerous”.

The Pentagon estimated 10,000 North Korean troops had been deployed to eastern Russia for training, a figure up from last week’s estimate of 3000 troops.

“A portion of those soldiers have already moved closer to Ukraine, and we are increasingly concerned that Russia intends to use these soldiers in combat or to support combat operations against Ukrainian forces in Russia’s Kursk Oblast near the border with Ukraine,” said Pentagon spokeswoman Sabrina Singh, using a term for a Russian region.

The Kremlin initially dismissed reports about a North Korean deployment as “fake news”.

But Russian President Vladimir Putin on Thursday did not deny North Korean troops were in Russia and said it was Moscow’s business how to implement a partnership treaty with Pyongyang.

Putin also said over the weekend that Moscow would respond accordingly if the US and its allies helped Ukraine strike deep into Russia, and that Moscow considers the West’s potential approval as “direct involvement of NATO” into the war.

The United States, however, has given no indication that it will approve Ukraine’s deep strike request.

A North Korean foreign ministry official did not confirm media reports about a troop deployment to Russia, but said if Pyongyang had taken such action, he believed it would be in line with international norms.

Ukrainian military intelligence said on Thursday that the first North Korean units had been recorded in the Kursk border region, where Ukrainian troops have been operating since staging a major incursion in August.

But the Pentagon declined to confirm that North Korean forces were already in Kursk.

“It is likely that they are moving in that direction towards Kursk. But I don’t have more details just yet,” Singh said.

Ukrainian President Volodymyr Zelensky said the move was an escalation by Russia.

Ukrainian Foreign Minister Andrii Sybiha said Kyiv had been warning about the deployment for weeks, and accused allies of failing to deliver a strong response.

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“The bottom line: listen to Ukraine. The solution: lift restrictions on our long-range strikes against Russia now,” Sybiha said on X.

North Korea and Russia have upgraded their military ties since their leaders met in Russia’s far east last year. They met again in June to sign a comprehensive strategic partnership that includes a mutual defence pact.

A flurry of bilateral visits of high-ranked officials have followed between the two countries, which share a small border.

North Korean Foreign Minister Choe Son-hui departed Pyongyang on Monday for her second trip to Russia in six weeks.

Rutte said the North Korean deployment was a sign of Putin’s “growing desperation”.

“Over 600,000 Russian soldiers have been killed or wounded in Putin’s war and he is unable to sustain his assault on Ukraine without foreign support,” Rutte said.

Zelensky’s chief of staff, Andriy Yermak, said sanctions alone would not be a sufficient response to North Korean involvement.

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Yermak said Kyiv needs “weapons and a clear plan to prevent North Korea’s expanded involvement”.

“The enemy understands strength. Our allies have this strength,” he said on X.

Reuters

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