South Korean President Park Geun Hye said she is open to a first formal meeting with Japanese Prime Minister Shinzo Abe, but stressed the need for progress on some long-standing issues for any summit to be meaningful.
Ms Park has not held bilateral talks with Mr Abe since she took office in 2013, due to disputes over Japan's war atrocities, particularly on the issue of "comfort women". The Korean peninsula was under Japanese rule from 1910 to 1945.
South Korea has held the position that Japan has not done enough to atone for the suffering of comfort women, while Japan believes it has expressed remorse and offered appropriate reparations.
Speaking at the Washingtonbased Centre for Strategic and International Studies on Thursday, a day before her meeting with US President Barack Obama, Ms Park said: "As to the question about holding a bilateral summit with Prime Minister Abe, I do feel that I can have such a meeting with him."
But she added that "in order for such a meeting to be significant, I think it's important that the two countries be able to move towards a more future-oriented change in our relationship... a meeting that does lead to progress on this (comfort women) issue can be characterised as a meaningful meeting".
The United States is eager to see improved ties between South Korea and Japan - two of its key Asian allies - given North Korean nuclearisation and China's growing assertiveness in the region.
Relations between South Korea and Japan were further strained in 2013 when Mr Abe visited the controversial Yasukuni Shrine, which honours Japan's war dead including convicted war criminals.
News reports have said Mr Abe will not visit the shrine this year to prevent derailing possible bilateral talks with South Korea and China.
Ms Park, who is currently on a four-day official visit to the US, said a trilateral summit between China, Japan and South Korea would be held in Seoul early next month after a hiatus of 3½ years.
"It will be an important occasion to pursue peace and stability in North-east Asia, as well as to improve Korea-Japan relations," she said. "I hope this trilateral summit will provide an opportunity for Korea and Japan to clear away obstacles hindering bilateral ties and thus hold sincere discussions on the way forward towards a common future."
Commenting on the trilateral summit, US Assistant Secretary of State for East Asian and Pacific Affairs Daniel Russel told a press conference: "I would say that we welcome that. We see that as an opportunity for enhanced consultation among the three major powers in North-east Asia."
He said the US had gone to great lengths to support better relations between Japan and South Korea.
"Japan and Korea are our two closest allies in North-east Asia, and their relationship and their ability to cooperate is a strategic priority for the United States," he said.
Ms Park also expressed support for the recently completed Trans-Pacific Partnership (TPP) trade deal, hinting that South Korea could join in the future. "Having already signed trade agreements with 10 of the 12 TPP member countries, I believe Korea is a natural partner for the TPP," she said.
Commenting on that issue, Mr Russel said: "President Obama has welcomed that interest. But the job at hand is completing the processes regarding TPP. The issue of additional negotiating partners lies beyond that."