South Korea countered that Japan is inappropriately meddling in the way Seoul accommodates its most important guests.

On Tuesday, President Moon Jae-in hosted the banquet for Trump and U.S. officials on a two-day trip to Seoul. The presidential office invited the 88-year-old Lee Yong-soo, who was forced into sex slavery for Japanese troops during World War II, to the dinner.

Lee is one of more than 30 living Korean victims, euphemistically called comfort women. She is known as an outspoken and vocal critic of Japan.

According to local media, Japan delivered its protest at Lee's attendance of the dinner to South Korea through diplomatic channels and demanded the deal the two countries reached in 2015 to "finally" and "irreversibly" resolve the comfort women issue should be faithfully enforced.

"Japanese officials view the invitation of Lee, one of the most vocal critics of Japan's handling of the issue, to the event as running counter to the spirit of the agreement," Kyodo news agency reported.

Japanese daily Sankei Shimbun also reported that Japanese Foreign Minister Taro Kono has delivered a protest to South Korea's Foreign Minister Kang Kyung-wha over the matter. The report has not been confirmed.

In response South Korea's foreign ministry said Thursday that it is inappropriate for Japan to take issue with how it prepares a state dinner and that it delivered its own stance on the matter through diplomatic channels.

"The food served at the dinner and those invitees were determined by reflecting all necessary factors," Noh Kyu-duk, foreign ministry spokesman, told a regular press briefing. "We do not think it is appropriate to take issue with that."

The former comfort woman Lee also expressed anger and strongly criticized Japan in an interview earlier in the day.

"Whether I go and meet such guests is none of their business. ... They are too arrogant," Lee said.

South Korea and Japan reached a deal in December 2015 under which Tokyo apologized for its colonial-era atrocities and agreed to contribute 1 billion yen (US$8.9 million) to a foundation dedicated to supporting the victims.

Saying that the deal lacks public consensus, the Moon Jae-in government, which took office in May, has been reviewing the process by which it was reached under the previous administration, hinting that it could be scrapped or revised.

Japan says that both countries have to faithfully enforce what was agreed upon by their governments.

Historians say more than 200,000 women, mostly Koreans, were coerced into sexual servitude in front-line Japanese brothels during World War II, when the Korean Peninsula was a Japanese colony. (Yonhap)