South Korea demands explanation and apology from Ukraine after Zelensky publicly revealed at UNGA that two captured North Korean soldiers had been transferred to Seoul.

South Korea says Ukraine itself requested secrecy over the handover, fearing domestic criticism about losing a POW swap opportunity.

Seoul agreed to protect the men's safety and their families in North Korea.

Ukraine denies any confidentiality deal existed.

Seoul called that denial "false" and said the disclosure was made without adequate consultation, damaging trust.

The presidential office is reviewing "additional measures."