The U.S. has estimated there are about 10,000 North Korean troops in Russia. Seoul and its allies assess that the number has increased to 11,000.

Some 8,000 North Korean troops are in Russia's Kursk region near Ukraine's border, US deputy ambassador to the UN says

North Korean troops have begun engaging in combat operations alongside Russian forces, the U.S. State Department said on Tuesday, expressing concern that Russia had turned to North Korea for soldiers to fight in its war with Ukraine.

North Korea ratified a defense treaty with Russia, state media reported Tuesday, formally deepening military cooperation that has seen Pyongyang send thousands of troops to help Moscow in its war against Ukraine.

"Today I can confirm that over 10,000 (North Korean) 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,

North Korea ratified a major defense treaty with Russia stipulating mutual military aid, the North’s state media reported Tuesday, as the U.S., South Korea and Ukraine say North Korea has sent thousands of troops to Russia to support its war against Ukraine.

The United States confirmed Tuesday that North Korean troops, who have been deployed to Russia's western front-line Kursk region, have begun engaging in combat operations against Ukrainian forces.