South Korea fights another war of history with Japan as Tokyo tries to register wartime coal mines and shipyards served by Korean slave laborers as UNESCO heritage sites, according to Yonhap News Agency.

The two Northeast Asian neighbors have already been in a dispute over Japan's refusal to properly apologize to the victims of Japan's sex slavery during World War II and compensate them.

Historians say more than 200,000 women, mostly Koreans, were forced to serve as sex slaves during the war, when the Korean Peninsula was under the Japanese colonial rule.

At issue is Japan's bid to register its early industrial facilities as UNESCO world heritage sites.

The 23 candidate sites, which Japan claims are symbolic of the "Meiji Industrial Revolution," include several coal mines and shipyards where tens of thousands of Koreans worked as slave laborers during Japan's imperialistic past.

"The UNESCO listing is a pet project of Prime Minister Shinzo Abe," a government source here said Tuesday. "Japan is lobbying very hard to get the sites registered."

The International Council on Monuments and Sites (ICOMOS), an expert group to review applications, is expected to decide whether to support Tokyo's move as early as next week.

It will then announce a decision in mid-May for recommendation to the World Heritage Committee. The panel plans to hold a meeting in Germany from June 28 to July 8.

South Korea is strongly protesting against Japan's attempt, saying it is a "matter of a moral problem."

Seoul's foreign ministry formed a task force to counter Tokyo's campaign.