A U.S. official said, "Thousands of North Korean troops are training in Russia...It is unclear whether the war will be deployed or not."

The U.S. government says thousands of North Korean soldiers are being trained in Russia over the North's sending of troops to Russia, which is at war with Ukraine.

Asked about North Korea's dispatch of troops to Russia, a senior U.S. government official said, "It has not been confirmed what the North Korean military's mission is and whether it will be deployed to combat Ukraine."

The official said that if North Korea sends troops, it shows Putin becoming more and more desperate in the war in Ukraine.

He also stressed that Russia is causing enormous casualties on the battlefield every day and that if Russia has to lean on North Korean troops, it is a sign of Russia's desperation.

Earlier, Defense Secretary Lloyd Austin confirmed North Korea's dispatch to Russia for the first time among U.S. government officials, saying there is evidence that North Korean troops are in Russia in Rome, Italy.