Magazines which feature raunchy girls on their front pages have been given six weeks by co-operative to cover them up in sealed "modesty bags" or be taken off sale in its stores.
Titles such as Front, Loaded, Nuts and Zoo have been given a deadline of September 9 to deliver the magazines in pre-sealed bags, the BBC reported.
According to the 4,000-outlet retailer, it was responding to concerns by its members, customers and colleagues about images of scantily clad women on covers.
One campaign group called for Co-op, which is owned and run by its more than seven million members, to stop selling such titles altogether.
The Co-op has introduced their own opaque screens on shelf to reinforce their existing policy limiting the display of such material.
However, campaign group Lose the Lads' Mags claimed that the Co-op was not going far enough, saying that they are attempting to sell their customers short.