SEOUL (Reuters) - Senior South Korean and Japanese officials will meet this week to discuss Japan's wartime sexual enslavement of Korean women, South Korea's Ministry of Foreign Affairs said on Sunday.

Ties between the two close U.S. allies have long been poisoned by what South Korea consider Japan's failure to atone for its wartime past, including the issue of so-called comfort women, forced to work in Japanese brothels.

The talks on Wednesday will be held a week or so before U.S. President Barack Obama will visit both countries. Obama brought together the leaders of the East Asian neighbors last month in the Netherlands.

Japan reportedly wanted the upcoming talks to include other issues including overlapping claims to some islands and North Korea, but South Korea's Yonhap news agency said they had agreed to focus on the "comfort women" as South Korea insisted.

Japan says the matter of compensation for the women was settled under a 1965 treaty establishing diplomatic ties. In 1995, Japan set up a fund to make payments to the women from private contributions, but South Korea says that was not official and therefore, insufficient.

South Korea's Ministry of Foreign Affairs said the two sides had agreed to more talks at various levels later.

(Reporting by Narae Kim; Editing by Robert Birsel)