What would a North Korean troop surge mean for Ukraine war?

North Korea is preparing a massive troop surge to help its ally Moscow in its war on Ukraine , with up to 50,000 North Koreans to be deployed in Russia , according to Ukrainian President Volodymyr Zelenskyy .

In late July, the Ukrainian leader said Russia wanted to bring in another 30,000 North Korean troops, before adding this weekend that Pyongyang decided to have between 30,000 and 50,000 North Koreans deployed on Russian territory. He did not specify if this number included the North Korean troops already taking part in the conflict.

In the comments published this weekend, Zelenskyy also warned North Korea was gaining valuable experience in modern warfare and urged South Korea to boost cooperation with Ukraine on air defense and drones. Two days later, Zelenskyy said Russia had received more North Korean ballistic missiles, which were allegedly used in an attack on Zaporizhzhia.

Russia and North Korea signed a defense pact in the summer of 2024, with North Korea starting to send combat troops to Russia several months later . Analysts believe some 14,000 to 15,000 personnel were deployed, mainly in the Kursk region.

Pyongyang later agreed to send another 6,000 sappers and military construction workers. North Korea has also supplied Russia with millions of artillery rounds and ballistic missiles, according to South Korean and Ukrainian authorities. South Korean intelligence estimates that around 6,000 North Korean soldiers have been killed or wounded.

On Thursday, Japan's Kyodo News cited Ukrainian military intelligence as confirming the upcoming North Korean surge. Ukrainian sources say up to 50,000 North Korean troops could be deployed to Russia by the end of November; The troops would reportedly take over duties in Russia's Kursk, Bryansk and Belgorod, freeing Russian forces for the Ukrainian front.

South Korean lawmaker Yu Yong-weon told DW the military cooperation between Russia and Korea was growing ever closer.

Yu is a former military journalist who visited Ukraine in 2025 and again in February this year. He said he heard claims of the North Korean surge during his most recent visit to the war-torn country.