KUALA LUMPUR - A move by Japanese convenience stores to stop selling adult magazines ahead of two major sports events could help to stop women being exploited for sex, campaigners said on Wednesday.

Two large chains, 7-Eleven Japan Co. and Lawson Inc. - which have some 34,000 stores combined - said they would no longer sell porn magazines as they look to clean up their image ahead of the 2019 Rugby World Cup and next year's Tokyo Olympics.

"This is certainly a welcome move," Kanae Doi, Japan director of the non-profit Human Rights Watch, told the Thomson Reuters Foundation by phone from Tokyo.

"It has been very shameful ... you can see pornography everywhere in Japan. Women are still seen as sex objects and not treated equally," she added.

The distribution of pornography, including sexually explicit manga comic books, is common in Japan. It has been blamed by activists for contributing towards sexual violence against women.

Japan was the last developed nation to criminalize possession of child pornography in 2014, as publishers opposed what they said were restrictions on freedom of expression.

Prime Minister Shinzo Abe has promoted policies to raise the social status of women, but Japan still has a poor record when it comes to gender equality, ranking 110 out of 149 countries in the World Economic Forum's 2018 Global Gender Gap report.

In separate announcements on Tuesday, the chains said the decision was to make their stores more family-friendly and in anticipation of an influx of tourists ahead of the two global events.

24-hour convenience stores are hugely popular in Japan, selling everything from coffee, alcohol, frozen meals and even spare work shirts.

Magazine racks are usually close to the front of the store and are not covered. Adult magazines are usually mixed in with those of other genres.

Widespread pornography in Japan is pushing some 500 women into the sex industry each year, where they are treated in a "degrading and demeaning" way, researcher Caroline Norma from the RMIT University in Australia said in emailed comments.

"Any measure to suppress the products and activities of the sex industry in Japanese society will ease an environment of sexual objectification and exploitation that is mostly unregulated and culturally celebrated."

Earlier this month a Japanese tabloid magazine caused public outrage with an article ranking five universities on how easy it was to persuade female students to have sex.