Foreign Minister Kang Kyung-wha has stressed the need for stern disciplinary measures over the leak of telephone talks held between South Korean and U.S. leaders by a diplomat serving at the South Korean embassy in Washington.

Speaking to reporters in Paris on Friday, Kang characterized the latest incident as a civil servant intentionally leaking a diplomatic document containing state secrets.

She said that incidents until now have been dealt with in accordance with their severity, but the latest case is on a whole different level.

Kang said that before leaving for Europe, she gave the order for the leak to be thoroughly investigated and the leaker sternly punished. 

She added that once an internal probe reveals more details, disciplinary measures will follow.

Regarding when the diplomat in question will be summoned back to Korea, Kang said an investigation is under way and it's difficult to comment, but when it finishes, more information could be disclosed to the public.

Earlier this month, Rep. Khang Hyo-shang of the main opposition Liberty Korea Party disclosed details from a leaked confidential phone conversation between President Moon Jae-in and U.S. President Donald Trump. Khang cited an unnamed diplomatic source in the U.S., who has since been identified as a diplomat at the South Korean Embassy, as the source of the leak.