Improved Korea-Japan ties to boost trilateral cooperation involving US: top security adviser

National Security Adviser Wi Sung-lac speaks during a press briefing at a hotel in Tokyo, Japan, Sunday. Yonhap

TOKYO — Improvement in Korea-Japan relations will help strengthen trilateral cooperation involving the United States, according to Wi Sung-lac, Korea's top security adviser to the presidential office, Sunday.

Wi emphasized that Saturday's summit between President Lee Jae Myung and Japanese Prime Minister Shigeru Ishiba holds strategic significance, saying it is expected to have a positive effect ahead of Lee's upcoming bilateral meeting with U.S. President Donald Trump in Washington on Monday (local time).

“Linking visits to Japan and the U.S. has effectively demonstrated the advancement of the trilateral cooperation between Korea, U.S. and Japan," Wi said during a press briefing at a hotel in Tokyo.

"In the past, when Korea-Japan ties were strained, it was often Washington that tried to lead the three-way cooperation. This time, Seoul has taken the initiative, and Japan has recognized that Korea values its relationship with Tokyo,” Wi explained.

Korea's top security official indicated that some Japanese media described Lee’s choice to visit Japan first for a bilateral talk before the U.S. as a “pleasant surprise," noting that going to the U.S. after improving relations with Japan should be seen as a positive move not only in Japan but also in the U.S.

"The U.S. places great importance on Korea-U.S.-Japan cooperation, and despite many unresolved issues between Korea and Japan, moving toward stronger collaboration is a positive step," Wi said.

“Our approach is that if Japan succeeds, Korea succeeds, and so does the U.S. While challenges remain, our efforts in Japan aim to create a virtuous cycle driven by positive momentum, generating the energy needed to tackle more difficult issues and ultimately achieve a win-win outcome for all.”

President Lee Jae Myung and Japanese Prime Minister Shigeru Ishiba move to a meeting room at the prime minister’s residence in Tokyo, Japan, Saturday. Yonhap

Wi noted that the two leaders spoke for a total of three and a half hours, adding that a small-group session, initially planned for just 20 minutes, extended to nearly an hour.

“In particular, in the small-group meeting, the president and the prime minister devoted considerable time to discussing relations with the U.S. and tariff negotiations with the U.S.,” Wi said, emphasizing that the two leaders acknowledged there are many tasks the two countries may respond to jointly amid rapidly changing circumstances.

Wi said Ishiba shared his own experiences in meeting with Trump, underscoring that summits reflect the individuality of each leader, so another country’s experience cannot be directly applied, though it serves as a useful reference.

“There were many tariff-related issues with the U.S., and the Japanese side mainly shared their experiences and impressions in the form of advice. Our president also asked follow-up questions, and since he is about to depart for the U.S., this will be of great help. We expressed gratitude to the Japanese side,” Wi elaborated.

President Lee Jae Myung and first lady Kim Hea Kyung, second from left, stand next to Japanese Prime Minister Shigeru Ishiba and his wife, Yoshiko Ishiba, during their meeting at the prime minister’s residence in Tokyo, Japan, Saturday. Joint Press Corps

Regarding the upcoming summit on Monday between Lee and Trump, Wi noted the three main themes of the talk will be stabilizing the economic and trade sector, modernizing the alliance and exploring new horizons of cooperation.

"These three themes are still being discussed, and agenda coordination is ongoing,” he said.

Lee is scheduled to depart Tokyo on Sunday afternoon and arrive in Washington later the same day (local time). On Monday morning, the two leaders will hold their first summit, followed by a working luncheon.