TOKYO • The Japanese government is demanding a United Nations envoy retract remarks that 13 per cent of schoolgirls in Japan are involved in forms of paid dating that can involve sex.

The foreign ministry said it had recently informed the UN Office of the High Commissioner for Human Rights that the comment, made in Tokyo last month, was "inappropriate and extremely regrettable".

It is "unacceptable" that the envoy cited "unreliable information" without a source, the ministry revealed in a statement on Monday.

Last month, Ms Maud de Boer-Buquicchio, the UN's special rapporteur on the sale of children, child prostitution and child pornography, touched on the Japanese social phenomenon of "enjo kosai", often translated as "compensated dating", during a press conference. "Some 13 per cent of the schoolgirls in Japan are involved in that kind of activity, which perhaps starts with a relatively innocent activity" such as men going for a walk with high school girls, she said.

The spat highlights what has come to be seen as a troubling aspect of the sexualisation of young girls in Japan, in which they are portrayed in the media in suggestive ways that have been largely accepted domestically.

In "enjo kosai", which emerged in the 1990s, older men pay teenage girls for dates which can involve sex, while the expression "JK" - a Japanese abbreviation for high school girls - refers to more organised and systematic operations in which girls can give massages, lie down next to men or accompany them for a stroll.

The United States Department of State last year said in a report that "enjo kosai... continues to facilitate the prostitution of Japanese children".

In response to the foreign ministry's protest, Ms de Boer-Buquicchio said she "received no official statistic on the scope of the 'JK business' in the country" during her trip.

"However, many of my interlocutors referred to it as a worrying trend which can easily lead to sexual exploitation of the minors involved in this lucrative business," she said.

"I made reference to estimates I had seen in open sources to highlight a phenomenon that must be urgently tackled."

The Guardian newspaper said Ms de Boer-Buquicchio also praised Japan for legislation passed last June forbidding the possession of child abuse images. But she warned that exploitation continues through the law's loopholes for manga comics and anime.

"When it comes to particular, extreme child pornographic content, manga should be banned," she said.

But artists hit back, claiming freedom of expression.

"There is no such thing as manga and anime child pornography," manga translator Dan Kanemitsu told The Guardian.

AGENCE FRANCE-PRESSE