There are risks of North Korea sending additional troops and military equipment to the Russian army,” Zelensky said. “We will have tangible responses to this.”

Secretive North Korea has one of the world’s largest militaries, with 1.28 million active soldiers, but unlike in Russia, the Korean People's Army (KPA) has no recent experience of combat. Pyongyang’s army is “thoroughly indoctrinated but with low readiness,” says Mark Cancian, from the Centre for Strategic and International Studies (CSIS).

While some Western officials initially viewed the arrival of North Korean soldiers in Russia as evidence of the Kremlin’s desperation, U.S. agencies now reportedly believe the idea was North Korea’s initiative,

After two years of intense courtship, progressing from warm words to vital weapons, summits in Pyongyang to 11,000 soldiers on the ground in Russia, the burgeoning relationship between Vladimir Putin and Kim Jong-un was signed in blood this week when the first stories emerged of North Korean casualties on the Ukrainian battlefield.

In one week there were more than a thousand North Koreans casualties in the fight with Russia against Ukraine. U.S. officials say they are sent into battle with little equipment or preparation.

Ukrainian President Volodymyr Zelenskiy has reported significant battlefield losses among North Korean troops fighting in Ukraine, claiming they are left unprotected by Russian forces. The statement sheds light on the challenges faced by foreign troops supporting Russia in the conflict and raises questions about the treatment and coordination of allied forces on the front lines.