Japan has stated it will not make changes to an apology issued in 1993 to the "comfort women" who worked as sex slaves for the military during World War II.

The apology, known as the Kono Statement, was issued by the Japanese government to thousands of women from several Asian countries that were forced to serve as sex slaves in brothels for Japanese troops during the '30s and '40s. The statement offered its "sincere apologies and remorse" and promised to acknowledge what happened, according to the AFP.

"I am not thinking of revising the Kono Statement," Chief Cabinet Secretary Yoshihide Suga said according to Bloomberg News.

Several women who said they were forced into servitude testified at a hearing in 1993. Suga said he will move forward with plans to verify evidence that supported the 1993 statement. He will present the results of the investigation to parliament if necessary, Bloomberg News reported.

The government's stance has increased tensions between China and South Korea, where most of the women came from. They also came from the Philippines, Indonesia and Taiwan, AFP reported.

The Chinese and South Korean governments have long maintained that Japan is denying this part of its history, according to AFP, and are now suspicious that Japan is looking to take back the apology.  

"If a nation continues denying past history, it will only end up driving itself into a corner and looking more miserable," South Korean President Park Guen Hye said in a speech earlier this month, Bloomberg News reported. It is "imperative to heal the wounds of the comfort women victims of the Japanese imperial military."

Nearly 200,000 women are estimated to have been made to have sex with Japanese troops. Some Japanese officials have said the women who worked in the brothels did so voluntarily and were not slaves, the Associated Press reported.  

Foreign ministers from Japan and South Korea are planning on holding talks this week to help ease tensions, according to AFP.

Suga did not say what would happen if evidence contradicting the Kono statement turns up, the AP reported.