Japanese Prime Minister Shigeru Ishiba welcomed South Korean President Lee Jae Myung in Tokyo on Saturday, marking Lee’s first official visit to Japan since taking office in June. The meeting was designed to reaffirm security cooperation and present a united front as both countries prepare for Lee’s high-stakes first summit with US President Donald Trump.

At the prime minister’s residence, the two leaders discussed regional security under their trilateral pact with the US, pledging closer coordination against North Korea’s missile and nuclear threats. Ishiba said:

“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.”

The leaders agreed to restart shuttle diplomacy, expand cultural and working holiday exchanges, and deepen cooperation in defence, economic security, artificial intelligence, and trade.

Lee’s election victory, following the impeachment of conservative ex-president Yoon Suk Yeol, had raised concerns in Tokyo over potential renewed tensions. Lee has previously criticised Japan’s wartime legacy and condemned recent visits by Japanese officials to a controversial shrine honouring war dead.

But in Tokyo, Lee struck a different tone, reaffirming support for closer ties with Japan. Japanese officials were quick to interpret his choice of Tokyo over Washington as his first destination as a positive signal.

For Ishiba, who is under pressure after July’s election setback, the summit was an opportunity to show diplomatic stability and recover political ground at home.

Despite lingering historical tensions, Japan and South Korea remain bound together by Washington’s strategic umbrella, hosting around 80,000 US troops, dozens of warships, and hundreds of aircraft. Both countries recently agreed with the Trump administration to set 15 percent tariffs on US goods, heading off the threat of harsher trade duties.

Lee summed up the outcome of the talks:

“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’s Tokyo stop comes just two days before his meeting with Trump in Washington, where the agenda will include China, North Korea, and Seoul’s financial contributions for US forces in Korea — a recurring demand from Trump.