The Japanese military's sexual slavery during World War Two will likely continue to be taught in Japan's middle schools in the new school year starting in April.

According to Japan's Sankei Shimbun on Wednesday, the Japanese Education Ministry recently dismissed a complaint filed by right-wing groups last December demanding that that the government push textbook maker Yamakawa Shuppansha to omit the part on sexual slavery.

Such references were lifted from Japanese school texts from 2004. The Yamakawa textbook, which included information on the issue, received government approval last year.

The book explains that women from Korea, China and the Philippines were recruited to work at battlefield brothels, or "comfort stations," and were known as "comfort women."

This prompted the complaint, in which the groups claimed that the term "frontline comfort women" could imply that the women were forced, which goes against Tokyo's position that no document has been found to prove their coercion.