Japan is planning to remove its deputy chief of mission to South Korea after he used a sexually explicit expression about President Moon Jae In to describe his approach to frayed bilateral ties, a government source said Monday.

Hiroshi Soma's remark that Moon's diplomatic efforts to mend frayed ties with Japan are tantamount to "masturbating" has angered Seoul and the president has decided not to visit Japan for the opening ceremony of the Tokyo Olympics on Friday.

Prime Minister Yoshihide Suga criticized Soma's remark, reported by South Korean broadcaster JTBC last week, as being "extremely inappropriate."

Regarding South Korea's announcement that Moon will not visit Japan for the Olympics, Suga told reporters he will seek to continue dialogue with Seoul while maintaining Tokyo's "consistent position."

The comment was "extremely inappropriate for a diplomat and extremely regrettable," Suga said, while declining to speculate on whether the remark influenced Moon's decision not to go to Japan.

Suga had previously said Japan would accommodate Moon if the South Korean president were to visit, without saying whether he would be willing to sit down for the first formal summit between the countries since December 2019.

Bilateral relations remain rocky due to disputes stemming from Japan's colonial rule of the Korean Peninsula between 1910 and 1945, including compensation for women coerced into working in military brothels and former wartime laborers.

Japan maintains all issues concerning properties and claims related to its colonial rule were settled under a bilateral agreement signed when the countries established diplomatic relations in 1965.

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