The backlash against Osaka Mayor and Nippon Ishin no Kai (Japan Restoration Party) coleader Toru Hashimoto escalated Tuesday over not only his remarks that Japan’s wartime sex slave system was necessary but also over comments to U.S. military brass in Okinawa that American soldiers should use more prostitutes.

The uproar began Monday morning when Hashimoto told reporters in Osaka that Japan’s wartime sex slave system, which forced thousands of girls and women from around Asia into prostitution for the Japanese military, had been necessary in order to maintain military discipline.

The women “were necessary in order to provide relaxation for those brave soldiers who had been in the line of fire,” Hashimoto said Monday morning.

Hours later, Hashimoto created another stir by saying that, on a recent trip to Okinawa, he’d met with U.S. military brass there and told them that, on mainland Japan, there were legal facilities for releasing sexual energy, and that unless soldiers in Okinawa made more use of similar facilities, it would be difficult to control the sexual energy of the marines.

“I’m not merely making conversation. I want them to use sex shops more,” Hashimoto told the Americans, referring to bordellos.

The remarks about the comfort women prompted criticism from Seoul. In a telephone interview with The Japan Times, a spokesman for the South Korean government said Hashimoto displayed a parochial view that showed an ignorance of human rights.

“The wartime violations of women is a grave violation of human rights that is widely shared by the international community. The remarks by Hashimoto reveal a serious lack of perception for women’s human rights,” the official said.

In Washington, the Pentagon called Hashimoto’s remarks in Okinawa ridiculous, and said there were laws against prostitution.

In Tokyo, senior government officials offered various reactions. While Chief Cabinet Secretary Yoshihide Suga offered no comment, Foreign Minister Fumio Kishida said Hashimoto’s comments were personal, but added he hoped there was no negative impact on Japan-South Korea relations.

Administrative reform minister Tomomi Inada, who before joining the Abe Cabinet lent her name to an advertisement in the U.S. media last year that denied government involvement in managing the brothels, appeared to agree with Seoul’s view.

“The comfort women system was a grave abuse of female . . . human rights,” she said.

Defense Minister Itsunori Onodera said the Abe Cabinet will not support Hashimoto’s views. But Shintaro Ishihara, who shares Nippon Ishin’s helm with Hashimoto, defended the remarks.

“Any military is commonly associated with prostitution. It’s a principle of history and by no means preferable. But Hashimoto is not saying anything wrong, basically,” he told reporters.

Hashimoto was unavailable for comment Tuesday. Through his Twitter account, though, he attempted to shift blame for his thinking by repeating earlier statements that a Cabinet ruling in 2007, during Shinzo Abe’s first stint as prime minister, had declared there was no proof that the central government kidnapped females and forced them to serve in military brothels.

“If proof does appear, we have to apologize. At the moment, it is the opinion of the government that there is none. However, a recent Cabinet decision seemed to indicate new proof would soon appear and I think it’s good that related organizations are making efforts to gather it,” he said.

As to his remarks to U.S. military brass in Okinawa during a visit over Golden Week, Hashimoto said Tuesday military brothels and government-sanctioned sex services for soldiers were nothing new. He noted that immediately following World War II, Japan established the Recreation and Amusement Association, a series of brothels for Allied troops in Tokyo.

“In my comments to U.S. military officials at Futenma, where I suggested the use of (bordellos), I did not mean to promote something illegal. The U.S. military forbids entrance into (bordellos) that are authorized by law, but even if you forbid entrance, that doesn’t mean that soldiers’ sexual desire will fall to zero, and I don’t know if such shops will help control sexual incidents,” Hashimoto said.

Official figures on the number of sexual assaults in Okinawa by U.S. military personnel are hard to come by. The prefectural government’s most recent data, from 2011, show there were no arrests for brothel-related offenses that year. Human rights groups and Okinawa officials concur that most incidents are either not reported or not prosecuted.

Hashimoto’s remarks about the comfort women and Okinawa bordellos are likely to make it even harder for Nippon Ishin to attract female candidates. Only about 10 percent of Nippon Ishin politicians are female, an area of concern that party advisers have long noted needs to change.