Five years ago at the 39th World Heritage Committee, UNESCO listed 23 places in Japan as World Heritage sites related to the Meiji Industrial Revolution.
But at seven of them, including on Hashima Island, Koreans were forced to work without being fed or paid properly and died of diseases, malnutrition and as the result of accidents.
The World Heritage Committee advised Japan to clarify the "full history" of each site.
Japan promised it will take such measures to show that Koreans were forced to work under such conditions and said an information center will be established to remember the victims.
However, the Industrial Heritage Information Center that Japan opened to the public two weeks ago is a long way from this promise.
The center did not install any exhibitions that depict the sufferings Koreans had to endure and even make claims to the contrary.
"I have never heard of brutalities on the Hashima Island during the war."
South Korea lodged a formal complaint against Japan and Seoul's Foreign Minister sent a letter to UNESCO Director-General Audrey Azoulay.
"Minister Kang Kyung-wha asked the agency to review cancelling the World Heritage designationand called for its active support that a resolution can be adopted to urge Japan to faithfully implement its pledge."
The recent flare-up of tension between Seoul and Tokyo comes on top of their year-long row over wartime forced labor and trade.
The tensions are expected to rumble on as Tokyo insists it has kept its pledge and that its stance has not changed.
Oh Jung-hee, Arirang News.