South Korean soldiers were guilty of abusing women in wartime, a Japanese mayor said in comments reported Tuesday, days after he provoked a storm by labeling WWII sex slaves a military necessity.

In a remark that provoked a sharp response from Seoul, further stoking tensions, Osaka mayor Toru Hashimoto said the South Korean military used women for sex during the Vietnam War.

Hashimoto said last week these women served a "necessary" role keeping battle-stressed soldiers in line. In the days since his original comments, Hashimoto has continued to fan the flames with new pronouncements, many of them on Twitter.

"It is true that we used women to solve the problem of sex on the battlefield," he told a party meeting on Monday, the Asahi Shimbun reported. "Having said that, America, Britain, Germany and France, and even the South Korean military in Vietnam after WWII, they all used women to address the issue."

There is no mainstream evidence that any modern military, other than that of Japan up to and during World War II, employed any system of sexual slavery.

In Seoul a South Korean foreign ministry spokesman said Japan's political classes needed to "correct anachronistic ways of thinking."

AFP