South Korea has demanded an official apology and explanation from Ukraine after President Volodymyr Zelenskyy publicly disclosed the transfer of two captured North Korean soldiers to Seoul.
The dispute centers on whether the governments had agreed to keep the transfer confidential, with Seoul accusing Kyiv of violating a nondisclosure agreement and Ukraine denying that such an arrangement existed.
The soldiers were captured by Ukrainian forces in January 2025 after fighting alongside Russia and had expressed a desire to resettle in South Korea.
South Korea's Foreign Ministry summoned Ukrainian Ambassador Andrii Vieshkin on Monday to protest what it described as Kyiv's unilateral disclosure and subsequent denial of a confidentiality agreement.
Senior presidential adviser Seong Ghi-hong expressed "strong regret" and said Ukraine's actions had damaged trust between the governments and could harm bilateral relations.
According to Seong, Seoul sought secrecy because of concerns about the soldiers' safety and the security of relatives remaining in North Korea.
He said Ukraine was also concerned about domestic criticism over giving up a possible opportunity to exchange the soldiers for Ukrainian prisoners held in Russia.
President Lee Jae Myung separately described the repatriation issue as highly sensitive.
Ukraine, however, has maintained that no secrecy agreement existed.
Zelenskyy revealed the transfer during his address to the United Nations General Assembly last week while discussing North Korea's military involvement in Russia's war against Ukraine.
The two soldiers had previously told media outlets while in Ukraine that they wanted to settle in South Korea.
Seoul had urged Kyiv not to return them to North Korea because of concerns they could face persecution.
South Korea's Ministry of Unification said Monday that authorities would review their cases under relevant laws and established practices, including legislation governing protection and settlement support for North Korean defectors.
The dispute comes as Seoul faces competing pressures surrounding the transfer, with the government concerned about its potential effect on inter-Korean relations while opposition politicians have criticized officials for keeping the soldiers' arrival from the public.