The deal included a Japanese government apology and an $8.8 million fund to help provide old-age care for survivors. But the agreement was immediately criticized in South Korea as insufficient; after Ms. Park was impeached in 2016 and Mr. Moon was elected as her successor, he pledged to review the deal.
A government-appointed panel concluded that South Korea had failed to represent the victims’ demands for Japan to take legal responsibility and offer official reparations.
Mr. Moon’s government said this week it would not renegotiate the deal, but on Tuesday, his foreign minister, Kang Kyung-wha, said the 2015 settlement could not be regarded as “a genuine resolution.” She added that South Korea would set aside its own $8.8 million fund for the victims, while discussing with Japan what to do with its contribution.
The next day, Mr. Moon called on Japan to “apologize with wholehearted sincerity to the victims and take this as a lesson so as to avoid the recurrence of such atrocities by making efforts in conjunction with the international community.”
Mr. Abe told journalists the request for an additional apology was “unacceptable.”
With the issue flaring a month before the opening ceremony of the Winter Games in Pyeongchang, South Korea, on Feb. 9, the Japanese news media reported that Mr. Abe might boycott the event.
Mr. Abe’s office said he was still deciding whether to go, given that a new session of Parliament was set to open on Jan. 22. Mr. Abe attended the opening ceremony at the Winter Olympics in 2014 in Sochi, Russia, even though he missed part of a parliamentary session to do so.
Many commentators in Japan supported Mr. Abe’s pushback on South Korea’s demand. Even an editorial in the left-leaning daily Asahi Shimbun, which is often critical of Mr. Abe, said Seoul’s latest statement on the 2015 accord “is not consistent with past developments,” adding that “Japan should consider all positive options for maintaining the agreement, without being told by South Korea what to do.”
Several analysts said Japan had repeatedly apologized to the women forced to work in Japanese military brothels, dating to a landmark statement 25 years ago in which Yohei Kono, then the chief cabinet secretary, acknowledged that the Japanese military had played some role in forcing Korean women to provide sex to soldiers.
Critics, however, noted that before becoming prime minister for the second time in 2012, Mr. Abe publicly questioned whether Japan’s imperial military actually coerced Korean women into sexual slavery.
Asking for a new apology indicates that the South Korean government is tacitly trying to revise the 2015 agreement that was meant to settle the issue, said Yoshiki Mine, a former official with the Japanese Foreign Ministry and now head of the Institute for Peaceful Diplomacy, a research organization. “The Korean position is so contradictory and so confusing and problematic,” Mr. Mine said.
Koichi Nakano, a political scientist at Sophia University in Tokyo, said the 2015 agreement was flawed because it was made between government leaders and did not include the voices of the victims.
“When you are talking about victims of human rights abuses, you can’t come to a resolution without their presence and consent,” he said. “As long as there are people who are not convinced that the apologies are heartfelt or that the compensation is adequate, then of course the aggressor would continue to ask for forgiveness and atonement.”
In South Korea, Mr. Moon’s party, the Democratic Party of Korea, said the 2015 agreement did not go far enough.
“What the victims of wartime sexual slavery want is recognition of legal responsibility,” Kim Hyon, a spokeswoman for the party, said in a statement.
Veteran diplomats in Japan said the two countries needed to figure out how to put the controversy behind them so they could focus on security cooperation and other current concerns.
The point of the 2015 deal “was that Japan and Korea would remove this issue from the centrality of our political relationship,” said Kazuhiko Togo, a former Japanese ambassador to the Netherlands and a professor of international relations at Kyoto Sangyo University. “We are fighting each other. That we have to stop.”
But sticking to the 2015 agreement, Mr. Togo said, “doesn’t mean that Japan is now in a position to forget.”