সিল demanded an official apology and explanation from Kyiv, accusing Ukraine of violating an agreement to keep confidential the transfer of North Korean prisoners of war to South Korea. Ukraine had initially requested confidentiality because of the sensitivity surrounding the transfer, and South Korea agreed, Sung Ki-hong, senior presidential secretary for public relations, said in a statement late Sunday. The dispute erupted after President Volodymyr Zelenskyy said in an address to the United Nations General Assembly last week that Ukraine had recently sent two North Korean soldiers captured by Ukrainian forces to South Korea.

North Korea had deployed thousands of troops to fight alongside Moscow’s forces and at least two were captured by Ukrainian forces in Russia’s Kursk region in January 2025. South Korea rejected Ukraine’s assertion that no confidentiality agreement existed, saying the incident had seriously damaged trust between the two governments and their bilateral relations.