Ukraine has denied Seoul’s claim that it apologized over the transfer of two North Korean prisoners of war to the South, blaming the diplomatic row on differing interpretations of confidentiality arrangements.

Ukrainian Foreign Ministry spokesperson Heorhii Tykhyi said in a briefing on Wednesday that Foreign Minister Andrii Sybiha merely expressed “regret that the situation had reached the point of an exchange of critical public comments” in an earlier message to his ROK counterpart Cho Hyun.

The officials comments come after Cho describedthe message as an insufficient apology earlier this week and warned of “firm measures,” including the possible recall