NATO Secretary-General Mark Rutte has confirmed that North Korean troops have been deployed to Russia days after Ukrainian military intelligence recorded the presence of North Korean units in the Kursk border region.

The Ukrainian military has been operating in the Kursk region since staging a major incursion in August.

Rutte said on Monday that the move represented “a significant escalation” of Pyongyang’s involvement in “Russia’s illegal war” in Ukraine, a breach of United Nations Security Council resolutions and a “dangerous expansion” of the conflict.

“The deepening military cooperation between Russia and North Korea is a threat to both Indo-Pacific and Euro-Atlantic security,” Rutte told reporters after NATO officials and diplomats were briefed by a South Korean delegation.

South Korean President Yoon Suk-yeol sounded the alarm about the troops during telephone calls with Rutte and European Commission President Ursula von der Leyen and added that Seoul would continue to consult closely with NATO.

US President Joe Biden also called the deployment of North Korean troops to Russia “dangerous”.

Earlier on Monday, the US Pentagon noted that North Korea has sent some 10,000 troops to train in Russia.

“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,” Pentagon Deputy Press Secretary Sabrina Singh told journalists.

Officials from Seoul have briefed #NATO Allies & Indo-Pacific partners on the North Korean troop deployment to Russia.

This is:

1. a significant escalation in DPRK’s involvement

2. yet another breach of UN resolutions

3. a dangerous expansion of Russia’s war. pic.twitter.com/0XEzz0d037

— Mark Rutte (@SecGenNATO) October 28, 2024

Kyiv has urged its allies to supply it with more weapons and allow deep strikes into Russia, which invaded Ukraine in February 2022. Moscow has warned Kyiv’s Western allies against providing long-range weapons to be used against Russia.

Ukrainian Foreign Minister Andrii Sybiha also highlighted that Kyiv had been warning about the North Korean deployment for weeks, yet there was no strong response from allies.

“Now NATO Secretary General confirmed this. The bottom line: listen to Ukraine. The solution: lift restrictions on our long-range strikes against Russia now,” he said on X.

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

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

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

The Kremlin had initially dismissed reports about a North Korean deployment as “fake news”. But last Thursday, Russian President Vladimir Putin did not deny that North Korean troops were in Russia and said it was Moscow’s business how to implement a partnership treaty with Pyongyang.

Moreover, 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.