SEOUL - Senior diplomats between South Korea and Japan held a closed-door meeting in Seoul to pre-arrange the thorny issue on Japan's wartime sex slavery of Korean women a day ahead of foreign ministers' meeting, Seoul's foreign ministry said Sunday.

The 12th round of director general-level meeting began at 3 pm local time (0600 GMT) on Sunday in the building of South Korea's foreign ministry to discuss the issue on comfort women, a euphemism for Korean women forced to serve in Japan's military brothels before and during World War II.

The South Korean side was led by Lee Sang-deok, director general of the ministry's Northeast Asia affairs bureau, while Kimihiro Ishikane, director general of the Japanese foreign ministry's Asian and Oceanian affairs bureau, led his country's delegation.

The closed-door meeting was held to pre-arrange each other's stances on the comfort women issue a day before the foreign ministers' meeting.

South Korean Foreign Minister Yun Byung-se and his Japanese counterpart Fumio Kishida will hold bilateral talks in Seoul from 2 pm on Monday. They are scheduled to have a joint press conference about an hour later.

During the first one-on-one summit meeting held in Seoul on Nov 2, South Korean President Park Geun-hye and Japanese Prime Minister Shinzo Abe agreed to speed up consultations on comfort women to reach an agreement by the end of this year.

After the summit meeting, two more rounds of the director general-level meeting had been held, ending up with no agreement.