South Korea has told Japan that it may send Prime Minister Lee Nak-yon to attend Emperor Naruhito's enthronement ceremony on Oct. 22, rather than President Moon Jae-in, according to diplomatic sources.

"The possibility of President Moon Jae-in attending has vanished," one of the sources in Japan said Monday.

Ties between Japan and South Korea have sunk to their lowest level in decades over South Korean court rulings that ordered Japanese firms to compensate Korean plaintiffs over wartime forced labor, and subsequent moves to have corporate assets seized.

The last time Moon and Prime Minister Shinzo Abe held talks was in September last year when they met on the sidelines of a regional economic forum in Vladivostok, Russia.

The Japanese side has ruled out a fresh summit in the absence of progress on the compensation issue, saying the South Korean side first needs to make efforts to resolve it.

It has made clear to Seoul that even if Moon were to attend the enthronement ceremony, a meeting with Abe would be unlikely.

According to the sources, meetings may be arranged between Lee and two former prime ministers — Yoshiro Mori, who once led a Japan-South Korea parliamentary league, and Yasuo Fukuda — both of whom belong to the same faction in the Liberal Democratic Party as Abe.

A precedent for Lee's possible visit was set when South Korea dispatched Prime Minister Kang Young-hoon to Emperor Emeritus Akihito's enthronement ceremony in November 1990.