NEW DELHI: The United States expressed concern over North Korea's decision to supply troops to Russia “to continue their brutal war against Ukraine”.

During a daily press briefing, State Department spokesperson Vedant Patel confirmed that thousands of North Korean troops in Russia have started “engaging in combat operations” alongside Russian forces on the Ukraine border.

Russia and North Korea both ratified a historic defence pact, deepening their mutual support and military cooperation. This treaty would see the two nations provide each other military support “without delay” if either nation comes under attack.

When asked about Russian President Vladimir Putin's rationalisation of the dispatch of North Korean troops by signing a military treaty, Patel said, “We are incredibly concerned by Russia’s decision to turn to the DPRK (Democratic People's Republic of Korea — North Korea's official name) to supply soldiers to continue their brutal war against Ukraine”.

“Today I can confirm that over 10,000 DPRK soldiers have been sent to eastern Russia, and most of them have moved to the far western Kursk Oblast, where they have begun engaging in combat operations with Russian forces,” he said.

The State Department spokesperson further revealed that the Russian forces have trained their North Korean counterparts in “UAV and basic infantry operations, including trench clearing, which are critical skills for frontline operations”.

“The United States is consulting closely with our allies and partners and other countries in the region on the implications of this, on these developments,” he added.

When asked about Russian Foreign Minister Lavrov's statement that the concept of North Korea’s denuclearisation is already a closed issue, Patel said “complete denuclearisation” of the Korean Peninsula remains the “cornerstone” of the US approach to the DPRK.