AFP/ Seoul

The leaders of South Korea and Japan broke an extended diplomatic freeze Monday with a rare summit at which they agreed to push for swift resolution of historical disputes that have tainted ties for decades.

In particular, South Korean President Park Geun-Hye and Japanese Prime Minister Shinzo Abe said they would step up efforts to settle the thorny issue of so-called Korean "comfort women" forced to work in Japanese military brothels during World War II.

It was their first ever one-on-one meeting. Park previously rebuffed all summit proposals, arguing that Tokyo had yet to properly atone for its wartime past and 1910-45 colonial rule over the Korean peninsula.

While it was never likely to mend all the many broken fences between the two neighbours, the summit was seen as an important step towards a more pragmatic partnership less encumbered by decades of rancour and bitterness.

Park began the meeting by stressing the need to "heal the wounds of the past" and the presidential Blue House said their talks did not shy away from tough issues.

"The two leaders agreed to speed up consultations to try to resolve the comfort women question as quickly as possible," the Blue House said, adding that Park had referred to the issue as the "biggest stumbling block" to friendly relations.

While Abe offered no new apology for Japan's wartime past, he told reporters afterwards that both sides had an obligation to "not leave obstacles for future generations".

Japan maintains that the comfort women issue was settled in a 1965 normalisation agreement, which saw Tokyo make a total payment of $800 million in grants or loans to its former colony.

The summit capped a series of moves in recent weeks -- prompted and pushed by their mutual military ally the United States -- to normalise relations.

Park met Abe as he arrived at the Blue House and the two smiled as they shook hands before the talks began.

It was a contrast to previous meetings between the two at multilateral events which had been studies in unsmiling, stony indifference, especially on Park's part.

- Curbing North Korea -

Since taking office in February 2013, Park has taken a particularly strong line on the issue of compensation for Korean comfort women.

It has been a politically popular stance in South Korea where Abe remains extremely unpopular, amid suspicions that he wants to water down Tokyo's past apologies for its wartime aggression.

But there has also been public support for a summit given the importance of the relationship between the two US military allies, who have strong trade links and a mutual interest in curbing the nuclear weapons ambitions of North Korea.

During the summit, both leaders reaffirmed their commitment to cooperating on the North Korean nuclear issue.

Their meeting was only confirmed days before amid reports of behind-the-scenes bickering over how Japan's wartime sex slavery might be addressed.

"Remember, this is the first summit between the two countries in nearly four years, so expectations need to be kept in check," said Hong Hyun-Ik, an analyst at the Sejong Institute think-tank in Seoul.

"What's important is creating a normal channel for dialogue to pave the way for more working-level discussions and coordination," Hong said.

The two leaders took part Sunday in a trilateral summit with Chinese Premier Li Keqiang -- the first meeting of its kind in more than three years.

In a joint statement, the leaders vowed to work together again on improving trade and security between the three largest economies in Northeast Asia.

The statement stressed the importance of "facing history squarely" but qualified that reference to old disputes by also underlining the necessity of "advancing towards the future".