Photo/IllutrationProtesters demand a repeal of the December 2015 bilateral agreement on "comfort women" during a rally in front of the Japanese Embassy in Seoul. (Asahi Shimbun file photo)

SEOUL--A South Korean task force examining the landmark 2015 agreement between Japan and South Korea that was considered the "final, irreversible resolution" of the wartime "comfort women" issue deemed the agreement "unbalanced."

The results of the study by the panel reporting directly to the South Korean foreign minister were released on Dec. 27.

As a candidate, South Korean President Moon Jae-in criticized and pledged to renegotiate the agreement entered into by his predecessor, Park Geun-hye.

A spokesman for Moon released a statement on Dec. 28 in which he said about the report, "It confirmed the existence of major defects in both the procedure behind the agreement as well as the contents itself."

The statement said that while the 2015 agreement carried the weight of being a formal promise between two governments, Moon would, "as president, make clear once again that the agreement would not resolve the comfort women issue."

The task force's report said that in addition to the formal agreement that was announced on Dec. 28, 2015, by then Foreign Minister Fumio Kishida and his South Korean counterpart, Yun Byung-se, there was a secret agreement between Japan and South Korea.

The agreement said Seoul consented to not using the term "sex slaves" when referring to the South Korean women who were forced to provide sex to Japanese military personnel before and during World War II.

That and other factors contributed to the conclusion that the burden on South Korean was disproportionate, leading to describing the agreement as unbalanced.

"Considering the effect that would be extended to the South Korea-Japan relationship, the government's position on the agreement will be decided on in a careful manner," Foreign Minister Kang Kyung-wha said at a Dec. 27 news conference.

In Tokyo, a statement was released in the name of Foreign Minister Taro Kono calling on Seoul to not attempt to change the 2015 agreement because that would make the bilateral relationship unmanageable.

While the South Korean presidential office is seeking to decide on a stance on the agreement before the start of the Pyeongchang Olympics in February, the release of the results will likely heighten criticism within South Korea toward the bilateral agreement.

The report said that the secret agreement revolved around three points that Japan asked of Seoul.

In addition to not using the term sex slaves when referring to the issue, Tokyo also asked that Seoul try to convince the Korean Council for the Women Drafted for Military Sexual Slavery, a support group which was behind the installation of a comfort women statue in front of the Japanese Embassy in Seoul, to support the agreement. Japan also asked Seoul to not provide support to other efforts to erect statues or monuments to comfort women in other nations.

The unbalanced agreement was due to Seoul's general acceptance, although in part somewhat passively, to the requests made by Tokyo.

The report also said the views of former comfort women were not taken into consideration because the agreement was reached, in large part, due to secret negotiations between Lee Byung-kee, a former South Korean ambassador to Japan who also served as chief of staff at the president's office under Park, and Shotaro Yachi, the director-general of the secretariat for the National Security Council and policy adviser to Prime Minister Shinzo Abe.

The report said the secret nature of the negotiations was a major reason many of the former comfort women rejected the agreement and added that controversy over the issue was bound to resurface despite the proclamation by the two governments of reaching a final and irreversible resolution.