South Korea, the United States and Japan are reportedly arranging a trilateral summit on the sidelines of the Group of Seven(G7) Summit in Hiroshima next month.

Japan's Yomiuri Shimbun daily reported on Thursday that coordination is under way to arrange the three-way summit on May 21, the last day of the G7 summit set to begin on May 19. 

South Korea is not a member of the G7, but Japanese Prime Minister Fumio Kishida invited President Yoon Suk Yeol as a guest last month. The White House said on Wednesday that U.S. President Joe Biden will also attend the G7 summit.

The trilateral summit, if realized, will come six months after the three leaders held a summit on the fringes of ASEAN-related gatherings in Cambodia last November.

Yomiuri quoted a Japanese government official as saying that the United States proposed the trilateral summit.