Key Points

"We are discussing with the Japanese side plans for Prime Minister Ishiba's visit at the end of September," the official said, adding that more details will be made public once finalised, Yonhap News Agency reported.

Ishiba is expected to make a two-day trip to the southern port city of Busan, starting Tuesday.

If confirmed, it will be a reciprocal visit after Lee's stop in Japan last month before heading to the United States for summit talks with US President Donald Trump.

Since taking office in June, Lee has pledged to maintain the thaw in ties and work closely with Tokyo to advance not only bilateral relations but also trilateral cooperation with Washington, while firmly addressing longstanding historical issues stemming from Japan's 1910-35 colonial rule of Korea.

Lee broke the precedents by choosing to visit Japan before the US in his first overseas trip as president, in an apparent move to demonstrate his commitment to aligning with the two countries.

The envisioned visit is expected to be the last trip for Ishiba as prime minister. Ishiba announced his resignation earlier this month following the ruling party's crushing election defeats both in the lower house last October and the upper house in July this year.

The ruling Liberal Democratic Party is set to elect a new leader October 4.

Earlier on September 23, the top diplomats of South Korea, the United States and Japan reaffirmed their "resolute" commitment to the denuclearisation of North Korea and highlighted the need to maintain sanctions against Pyongyang, a joint statement stated.

The statement came after South Korea's Foreign Minister Cho Hyun, US Secretary of State Marco Rubio and Japanese Foreign Minister Takeshi Iwaya met on the sidelines of the UN General Assembly for talks on their partnership and other shared issues, including North Korea's nuclear threats.

North Korean leader Kim Jong-un has suggested he is open to engaging in dialogue with President Donald Trump's administration if Washington drops its denuclearization demand, saying he has no intention of relinquishing his nuclear stockpiles.

"The Secretary and Foreign Ministers reaffirmed their resolute commitment to the denuclearization of the Democratic People's Republic of Korea (DPRK) in accordance with relevant United Nations Security Council (UNSC) resolutions, while continuing to make efforts to maintain peace and stability on the Korean Peninsula through dialogue and diplomacy," the statement read, referring to North Korea by its official name.

"They emphasised the need to address together the DPRK's nuclear and missile programs and to maintain and strengthen the sanctions regime against the DPRK by responding firmly and in cooperation with other countries to violations and evasions of the relevant UNSC resolutions."

- IANS