Ukrainian President Volodymyr Zelenskyy said Monday that more than 8,000 North Korean troops are now in Russia. He also said Russia is preparing to bring in another 10,000 North Korean soldiers.

Zelenskyy said these figures come from “new data” collected by his government about North Korean troop movements. He explained that North Korea is selecting these additional soldiers for training before sending them to Russia. The soldiers would receive training first and then be sent to support Russia in the war.

This is not the first time Zelenskyy has warned about North Korean soldiers joining Russia’s war. Back in August, he warned that North Korea could eventually send up to 50,000 soldiers to fight alongside Russian forces. At that time, he also asked South Korea to help Ukraine improve its air defense systems against Russian attacks.

South Korea has already provided support to Ukraine. In July South Korea announced a $100 million aid package for the Ukraine. However, the package did not include weapons and focused on non-lethal support instead.

Zelenskyy’s latest comments came during a tense period between Ukraine and South Korea. Last week, he said Ukraine had handed over two captured North Korean soldiers to South Korean officials. He shared the news during a speech at the United Nations General Assembly in New York.

South Korea was unhappy with the way the news became public. South Korean officials said they regretted Zelenskyy’s announcement because the both countries had reportedly agreed to keep the transfer of the soldiers private. South Korea also rejected a statement from Ukraine’s presidential office that said no such agreement existed. Seoul called the statement false.

A South Korean lawmaker named Yu Yong-weon, who belongs to the country’s main opposition party, later shared photos showing the two North Korean prisoners. He said he took these photos himself during a visit to a prisoner-of-war camp in Ukraine back in February.

North Korea’s role in the war goes back to 2024. Ukrainian and South Korean officials estimate that North Korea has sent between 14,000 to 15,000 troops to support Russia since then. Most of these soldiers were sent to Russia’s Kursk region, where they helped Russian forces push back Ukrainian troops.

Beyond just sending troops, North Korea has also supported Russia’s war effort in other major ways. According to Ukrainian and independent assessments, North Korea has supplied Russia with millions of artillery and mortar rounds. North Korea has also sent ballistic missiles, long-range artillery systems, and multiple-launch rocket systems to support Russian forces on the battlefield.

Zelenskyy also claimed that Russia has been giving North Korea valuable technology in return for troops and weapons. He specifically pointed to Shahed-style attack drones, saying North Korea is now producing these weapons on its own country with help from Russian technical experts.

This troop buildup did not happen overnight. In late 2024, U.S. officials confirmed that North Korea had sent thousands of soldiers to Russia’s front lines near Kursk. It was the first time since Russia’s full-scale invasion began in 2022 that another country had sent a large number of ground troops to fight alongside Russian forces.

The growing military partnership between Russia and North Korea continues raising serious concerns among Ukraine’s allies about how much closer these two countries may become in the future.