A dozen Korean victims of Japan's wartime sex slavery said Tuesday they will bring Japan to a U.S. court for financial compensation for the atrocities done to them.

The 12, including Yoo Hee-nam and Kang Il-chul, will lodge a civil suit at a California district court on July 1, Ahn Shin-kwon, director of the House of Sharing, told reporters at a news conference, quoting the victims.

They will seek $2 million each for the wartime atrocities committed by Japan and its companies "and their continued denial of instigating them," Ahn said.

The shelter decided to take the case to the U.S. because previous attempts to solve it in South Korea or Japan failed, he said.

Historians estimate that more than 200,000 women, mostly Koreans, were either kidnapped or deceived by the Japanese into working at their frontline military brothels during the war.

Two of the plaintiffs -- Kim Soon-deok and Choi Seon-sun -- have passed away since the home started filing the document, so they will be represented by their sons, Yang Han-seok and Wang Sang-mun, respectively, Ahn said.

The move comes as South Korea and Japan mark the 50th anniversary of their normalization of ties this year.

On June 22, 1965, Japan and South Korea agreed to nullify a treaty that annexed Korea to Japan. Korea was a Japanese colony from 1910-45.

Kim Hyung-jin, an attorney representing the "comfort women," stressed that the plaintiffs weren't after the money.

"Money is absolutely not the point," he said. "The point is that Japan admits to its war crimes and offers a sincere apology."

The House of Sharing has tried to bring Japan to a South Korean court since 2013 but to no avail.

Representatives from the Japanese government failed to show up at the first conciliation hearing between Japan and the former sex slaves in Seoul last Friday.

Japan claims it made sufficient reparations when it paid South Korea a lump sum of $500 million in 1965.

The South Korean government only has 238 sex slaves on file and of those, only 50 are still alive. (Yonhap)