South Korean President Moon Jae-in (MOON JAY'-een) says the country's 2015 agreement with Japan to settle a decades-long impasse over Korean women forced into wartime sexual slavery is seriously flawed.

Moon's statement Thursday in which he vows unspecified follow-up measures to meet the victims' demands potentially throws the future of the deal in doubt, two years after both countries declared it as "final and irreversible."

The statement came a day after a state-appointed panel concluded that Seoul's previous conservative government failed to properly communicate with the victims before reaching the deal.

The Foreign Ministry says government officials will hold extensive discussions with victims and experts before deciding whether to pursue changes to the deal.

Japanese officials have said a renegotiation is unacceptable.