SEOUL - Japan's prime minister must heal the wounds over "comfort women", most of whom were Korean and forced into prostitution in Japan's military brothels before and during World War II, South Korean President Park Geun-hye said on Friday.

The neighbours have struggled to find common ground over Japan's 1910-1945 colonisation of Korea, particularly the issue of "comfort women", as they are euphemistically known, with the issue long an obstacle to better ties between the US allies.

"As the Japanese prime minister and I agreed to expedite consultations for the early resolution of the issue ... I believe now is high time to make a decision to attend to the wounds from the past and heal them," Park said on Friday in an email interview with news agencies, including Reuters.

"Dragging on without acknowledging the problem goes against the sentiment commonly shared by all peoples around the world," she said.

Park and Japanese Prime Minister Shinzo Abe met as leaders for the first time on Nov 2 and they agreed to resolve as soon as possible the dispute over the women.

South Korea has urged Japanese leaders to issue a formal apology and offer compensation acceptable to the surviving women and the Korean people.

Japan considers the issue legally settled by a 1965 diplomatic treaty and said it stands by a 1993 government apology. It worries that even if it takes fresh steps, South Korea will decline to bring the issue to a close.

Park also reiterated her willingness to meet North Korean leader Kim Jong Un to discuss improving ties between the rival Koreas, but said Pyongyang must show it is serious about ending its nuclear programme.