Lee’s visit comes two days before his crucial first summit in Washington, DC with US President Donald Trump.
Japanese Prime Minister Shigeru Ishiba has hosted South Korean President Lee Jae Myung in Tokyo for a visit aimed at reaffirming security cooperation and showcasing friendly ties between the two East Asian neighbours facing common challenges from their mutual ally, the United States.
On his first official visit to Japan since taking office in June, Lee met Ishiba on Saturday at the premier’s residence to discuss bilateral ties, including closer security cooperation with the US under a trilateral pact signed by their predecessors.
“As the strategic environment surrounding both our countries grows increasingly severe, the importance of our relations, as well as trilateral cooperation with the United States, continues to grow,” Ishiba said in a joint announcement with Lee after their meeting.
The leaders agreed to resume shuttle diplomacy, expand exchanges such as working holiday programmes, and step up cooperation in defence, economic security, artificial intelligence and other areas. They also pledged closer coordination against North Korea’s nuclear and missile threats.
大韓民国 李在明大統領をお迎えしました。就任後初の二国間訪問先に日本を選んでいただき、6月のカナダ以来の面会となります。新たな時代のニーズに沿った日韓関係を築いていきたいと思います。 pic.twitter.com/DVFAgKVJgA
— 石破茂 (@shigeruishiba) August 23, 2025
The snap election victory of the liberal Lee – following the impeachment of conservative President Yoon Suk Yeol for declaring martial law – raised concerns in Tokyo that relations with Seoul could sour.
Lee has criticised past efforts to improve ties strained by lingering resentment over Japan’s colonial rule. The South Korean government last week expressed “deep disappointment and regret” after Japanese officials visited a shrine in Tokyo to Japan’s war dead that many Koreans see as a symbol of Japan’s wartime aggression.
In Tokyo, however, Lee reaffirmed support for closer relations with Japan as he did when he met Ishiba for the first time in June on the sidelines of a Group of Seven (G7) summit in Canada.
Lee’s decision to visit Tokyo before Washington has been well received by Japanese officials, who see it as a sign Lee is placing great importance on relations between the two neighbours.
For Ishiba, who faces pressure from right-wing rivals within his governing party to resign over its July election loss, Lee’s visit and a successful summit could shore up his support.
Despite their differences, the two US allies rely heavily on Washington to counter China’s growing regional influence. Together, they host about 80,000 US soldiers, dozens of US warships and hundreds of military aircraft.
Japan and South Korea also share common ground on trade, with both agreeing to 15 percent tariffs on US imports of their goods after Trump had threatened steeper duties.
We “agreed that unwavering cooperation between South Korea, the US and Japan is paramount in the rapidly changing international situation, and decided to create a virtuous cycle in which the development of South Korea-Japan relations leads to stronger cooperation”, Lee said alongside Ishiba.
Lee’s visit comes two days before his crucial first summit in Washington with US President Donald Trump. The two men are expected to discuss security concerns, including China, North Korea, and Seoul’s financial contribution for US forces stationed in South Korea – something the US leader has repeatedly pressed it to increase.