On his first official visit to Japan since taking office in June, Lee will meet prime minister Shigeru Ishiba at the premier’s residence in Tokyo to discuss bilateral ties, including closer security cooperation with the US under a trilateral pact signed by their predecessors.

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 1910–45 colonial rule of the Korean Peninsula.

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.

So far, however, Lee has said he backs closer relations with Japan, including in his first meeting with Ishiba on the sidelines of a Group of Seven summit in Canada in June.

Despite their differences, the two US allies rely heavily on Washington to counter China’s growing regional influence.

Together, they host around 80,000 US troops, dozens of American warships and hundreds of military aircraft.

In Washington, Lee and Trump 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.

Japan and South Korea also share common ground on trade, with both agreeing to 15% tariffs on US imports of their goods after Trump had threatened steeper duties.