Tokyo Report | Diplomacy | East Asia

The Geopolitical Circumstances of Japan-South Korea Rapprochement

The latest Lee-Takaichi summit highlighted not only their warm personal rapport but their priorities: energy and economic security.

Japanese Prime Minister Takaichi Sanae and South Korean President Lee Jae-myung attend a summit meeting in Andong, South Korea, May 19, 2026.

On May 19, South Korean President Lee Jae-myung and Japanese Prime Minister Takaichi Sanae met in Andong, Lee’s hometown, as part of their shuttle diplomacy. This marks their fourth meeting in just six months. The two leaders had already met this January in Takaichi’s hometown of Nara. On average, they have met once every two months since Lee’s inauguration.

The frequency of these meetings, combined with the visibly warm rapport between Lee and Takaichi, is by itself promising for bilateral relations. Despite early concerns over the ideological distance between them, Lee and Takaichi have maintained a notably cordial and cooperative relationship. Their meetings at APEC and other international gatherings have projected personal warmth, while both governments have generally exercised a degree of diplomatic restraint on historically sensitive issues. Lee has avoided actions such as a presidential visit to Dokdo, while Takaichi refrained from dispatching a ministerial-level representative to Takeshima Day. This mutual restraint has helped preserve diplomatic momentum at a time when both governments increasingly recognize the strategic value of closer cooperation.

The symbolism of these reciprocal hometown visits is particularly meaningful. This is the first time a Korean and Japanese leader have visited one another’s hometowns, lending the diplomacy a more personal character that helps deepen interpersonal trust. Andong itself is a historically meaningful place in Korea, home to multiple UNESCO World Heritage sites and the birthplace of many prominent Confucian scholars of the Joseon dynasty as well as independence fighters during Japanese colonial rule.

At the summit, the two leaders agreed to cooperate on strengthening the resilience of the energy supply chain and in the fields of artificial intelligence and economic security. South Korea and Japan share similar vulnerabilities as energy-importing states that are highly exposed to geopolitical instability in the Strait of Hormuz. This summit produced agreements on supply chain collaboration based on deeper information-sharing and communication regarding oil supplies, strategic reserves, and crude oil and petroleum product swaps. 

Lee and Takaichi also reaffirmed stronger security coordination and mentioned the gradual institutionalization of progress through the elevation of regular security talks to the vice-ministerial level from director-general level. However, the most politically manageable progress in bilateral cooperation is likely to emerge in economic security, technological cooperation, and maritime coordination rather than overt military integration. Military cooperation remains politically sensitive in South Korea, where concerns persist that Japan’s........

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