A diplomatic row between Kyiv and one of its Asian supporters has burst into the open, after South Korean President Lee Jae Myung threatened unspecified measures against Ukraine unless it apologises for publicly revealing the secret transfer of two North Korean soldiers captured while fighting for Russia. The dispute, over two prisoners who have become a symbol of Pyongyang's entry into Vladimir Putin's war, now risks costing Ukraine goodwill in Seoul at the very moment it needs every partner it can get.
Lee demands an apology as Seoul summons Kyiv's envoy
Writing on X on Friday, President Lee said South Korea would take "additional measures" if Ukraine continued to refuse to acknowledge what Seoul says was an agreement to keep the transfer confidential and to issue a public apology. He also expressed "grave regret" over Ukrainian remarks about the prospect of an imminent military clash between North and South Korea, which he said amounted to encouraging war on the Korean Peninsula.
Seoul has summoned Ukraine's acting ambassador and demanded an official explanation and an apology, accusing Kyiv of breaking a non-disclosure understanding and then falsely denying that one existed. A senior South Korean official said the transfer was meant to stay secret for security, diplomatic and humanitarian reasons, including the safety of the two prisoners and their families back in North Korea.
Ukraine says no such confidentiality agreement existed. Foreign Minister Andrii Sybiha tried to defuse the row on Thursday, telling journalists: "I would not like to call this an incident. Let's say, it's a diplomatic misunderstanding." He added: "For us, South Korea is an important country. And I really hope for momentum, continuation, and concrete results that we are truly achieving with them."
Two prisoners at the centre of a much bigger war
The two soldiers were captured by Ukrainian forces in January 2025 in Russia's Kursk region — the first North Korean troops taken alive since Pyongyang entered the war in 2024 in support of Moscow. Both men later expressed a desire to go to South Korea, and Seoul had refused to confirm their arrival, citing the risks to them and their families.
President Volodymyr Zelensky disclosed the transfer himself while addressing the United Nations General Assembly last month — the announcement that triggered Seoul's fury. Zelensky has this week also said that more than 8,000 North Korean troops remain in Russia and that 10,000 more are being trained for a future deployment, figures Kyiv presents as proof that the war is no longer a bilateral conflict.
North Korea has signed a strategic partnership agreement with Russia that includes a mutual defence pact, and dispatched an estimated 14,000 troops to help Moscow evict Ukrainian forces from the Kursk region. For Kyiv, the prisoners are evidence of that bargain; for Seoul, they are a humanitarian and diplomatic liability.
What Ukraine stands to lose
The timing could hardly be worse. South Korea has supported Ukraine with humanitarian and financial assistance since Russia's full-scale invasion in 2022, and in July pledged a further $100 million in non-lethal assistance. Cho Han-bum, a senior fellow at the Korea Institute for National Unification in Seoul, noted that any retaliatory measures would most likely involve the support Seoul already provides to Ukraine. "Ukraine has more to lose than South Korea because it is receiving support from Seoul," Cho said.
The row also lands on a sensitive desk in Seoul. President Lee's administration has sought to reduce tensions with North Korea and is still managing the political fallout from a recent landmine incident in the demilitarised zone — the last thing it wants is to be dragged, publicly, into a quarrel that touches the peninsula's own fragile calm.
Kyiv is working to mend ties, and Sybiha's conciliatory language suggests it knows the stakes. But the episode is a reminder of how far Putin's war now reaches: two wounded conscripts from North Korea, captured in a Russian border region, have managed to strain relations between two capitals thousands of miles apart — neither of which started the fight Moscow chose to internationalise.
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