South Korea and Japan said Monday they had agreed to resolve a decades-long impasse over Korean sex slaves, euphemistically known as ‘comfort women’, who were forced into Japanese military-run brothels during World War II, reported France 24.

The longstanding issue was one of the biggest sources of friction in ties between Seoul and Tokyo, two thriving democracies, trade partners and staunch US allies who have seen animosity rise since the 2012 inauguration of hawkish Japanese Prime Minister Shinzo Abe.

On Monday, Japanese Foreign Minister Fumio Kishida said Abe was offering an apology and that Tokyo would finance a 1 billion yen aid fund for the elderly former sex slaves to be set up by South Korea.

‘Prime Minister Abe, as the prime minister of Japan, once again expresses his feeling of heartfelt apology and remorse to all those who, as ‘comfort women’, experienced much suffering and incurred incurable psychological and physical wounds,’ Kishida Kishida told a news conference after a meeting with his South Korean counterpart, Yun Byung-se.

Yun said the agreement was ‘final and irreversible’, provided Japan faithfully implements its promises.

Legal responsibility

Japan had high hopes of a breakthrough on the thorny issue after the two regional rivals resumed talks last month following a more than three-year hiatus. Tokyo had been heartened by courts in Seoul recently refusing to review a complaint by a South Korean who sought individual compensation for Japan’s forceful mobilisation of workers during colonial days.

There has long been resistance in South Korea to past Japanese apologies because many wanted Japan to acknowledge that it has a legal responsibility for the women. Japan, for its part, had long argued that the issue was settled by a 1965 treaty that restored diplomatic ties and was accompanied by more than $800 million in economic aid and loans from Tokyo to Seoul.

It was not immediately clear if and how Monday’s deal included some form of legal responsibility for Japan.

US pressure

Historians say tens of thousands of women from around Asia, many of them Korean, were sent to frontline military brothels during World War II to provide sex to Japanese soldiers. In South Korea, there are 46 such surviving former sex slaves, mostly in their late 80s or early 90s.

Many South Koreans feel lingering bitterness from the legacy of Japan’s brutal colonial occupation of the Korean Peninsula from 1910-1945. But South Korean officials have also faced calls to improve ties with Japan, the world’s third biggest economy and a regional powerhouse, not least from US officials eager for a strong united front against a rising China.

Better relations between South Korea and Japan are a priority for Washington. The two northeast Asian countries together host about 80,000 US troops and are members of now-stalled regional talks aimed at ending North Korea’s nuclear ambitions in return for aid.