One of the largest magazine retailers in the U.K. has ordered magazines with overt sexual imagery to cover up their front covers with "modesty bags" or risk being withdrawn from sale.
So-called "lads' mags" - publications marketed primarily to men - such as Zoo, FHM, Nuts and Loaded have been a staple on supermarket shelves for the last few decades and have become synonymous with the sexual content and glamour model photos displayed on their front covers.
Supermarket chain the Co-operative gave an ultimatum to publishers on Monday, telling them to deliver the magazines in pre-sealed bags designed to obscure the front cover.
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If the companies do not comply before September 9 then the Co-operative - one of the U.K.'s largest magazine retailers - has threatened to cease selling the magazine at the 4000 plus stores it currently operates.
"As a community-based retailer we have listened to the concerns of our customers and members, many of whom say they object to their children being able to see overt sexual images in our stores," Steve Murrells, the chief executive of retail for The Co-operative Group, said in a press release on Monday.
"Whilst we have tried to mitigate the likelihood of young children seeing the images with a number of measures in-store, the most effective way of doing this is for these magazines to be put in individual, sealed modesty bags."
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As an interim measure, the Co-operative has introduced opaque screens on shelves to reinforce its existing policy limiting the display of such material.
The Minister for Women and Equalities, Jo Swinson MP, said on Monday that she welcomes the move and hoped other retailers will follow suit.
"Many parents aren't comfortable with the way that sexualized imagery has become like wallpaper - everywhere from the bus stop to the corner shop," she said.
"Adults should be left to make their own decisions about what legal sexual images they look at, but the place for these is not next to the sweets at children's eye-level."
The decision by the retailer is in line with recommendations from a parliamentary review two years ago which recommended a clampdown on sexualized "wallpaper" surrounding children. However, the move goes against existing guidelines for retailers which say that men's lifestyle magazines should not be placed next to children's' magazines or be at a child's eye level.
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A spokesperson for Bauer Media, the publisher of Zoo magazine told CNBC that it was aware of the Co-operative's request for the magazine to be put in sealed modesty bags, but supported the existing best-practice guidelines for the display of men's magazines.
"We are sensitive to the mood of the public, to that end we have responded accordingly and have changed ZOO magazine's cover imagery and phrasing," it said.
"We already have agreements in place with all major retailers, including Co-op, to ensure Zoo magazine is displayed appropriately and we work closely with all our retailers to ensure they are adhered to."
—By CNBC.com's Matt Clinch. Follow him on Twitter @mattclinch81