An elderly South Korean woman who was forced into sexual slavery for Japanese soldiers during World War II plans to speak about the issue in the United States and Japan, an activist said Friday.

Kang Il-chul plans to visit Atlanta and New York from Aug. 1-11 to speak about the wartime atrocities, said Ahn Shin-kwon, director of the House of Sharing, which houses a group of victims of sex slavery.

During the visit, Kang will also explain the background of a lawsuit lodged against Japan by the victims at a San Francisco regional district court on July 13.

Two former sex slaves lodged a lawsuit against Japanese Prime Minister Shinzo Abe, Japanese firms that enslaved Koreans for forced labor during the war, and conservative Japanese newspaper Sankei Shimbun, which has called former sex slaves "prostitutes" in its articles.

From September to November, Kang will also visit major cities in Japan, including Tokyo, to tell her story.

Kang visited the White House and the State Department last year to meet with officials as part of efforts to win their support on the issue.

The issue has gained urgency as the number of living victims has shrunk. In 2007, more than 120 South Korean victims were alive, but the number has since dropped to 48, with their average age standing at nearly 90.

Historians estimate more than 200,000 women, mostly Korean, were forced to work at front-line brothels for Japanese soldiers during the war.

South Korea demands Japan acknowledge state responsibility for the sex slaves, while Japan insists the issue was settled under the normalization treaty of 1965.

The sex slaves have been one of the knottiest issues between South Korea and Japan. (Yonhap)