The new head of NATO says Russian President Vladimir Putin has been unable to sustain his assault on Ukraine without help. Secretary General Mark Rutte confirmed on Monday that North Korean troops have been sent to western Russia. He followed other officials in saying they are in Kursk, an area that has come under attack from Ukrainian forces.

Rutte said a delegation from South Korea briefed NATO's decision-making body, the North Atlantic Council, and representatives of Indo-Pacific partners Japan, Australia, and New Zealand on the deployment. "The deepening military cooperation between Russia and North Korea is a threat to both the Indo-Pacific and Euro-Atlantic security," Rutte said. "It undermines peace on the Korean Peninsula and fuels the Russian war against Ukraine."

Rutte called the deployment "a dangerous expansion" of the war. He called on Russia and North Korea to "cease these actions immediately."

Officials with Ukraine's defense intelligence agency released what they claim is an intercepted radio communication. They said the recording suggests Russian officials are using private trucks to transport North Korean soldiers to the front lines.

Pentagon spokesperson Sabrina Singh said US defense leaders are "increasingly concerned" those troops will be used in combat. She said Ukrainian forces would not face any new restrictions on using American weapons against North Korean soldiers should they enter the fight.