The banned image shows a woman wearing lingerie and stockings kneeling on a bed with her back arched, legs wide apart and with one arm behind her head and the other on her thigh.
Complaints about the unsuitability of other images used in the outdoor campaign that also featured women in lingerie were not upheld.
The ASA ruled the images did not objectify women as it was “reasonable to feature models in underwear for a lingerie ad”.
The ruling follows a similar ban on a Lynx ad last week and demonstrates the ASA’s tougher line on “untargeted outdoor advertising” following its own research and the Government commissioned Bailey Review into the sexualisation of childhood.
David Cameron appointed Mothers Union chief Reg Bailey to head a review last year following growing concern of the impact of unrestricted sexual imagery becoming commonplace in the media environment.
“These rulings [on M&S and Lynx] are useful examples to the industry of the tougher line we’re taking on ads that are likely to be seen by children, following our announcement in October,” says an ASA spokesman.