The decision follows complaints from parents that their children were planning to re-enact the scene in the bath.
The ad, created by Publicis, received 31 complaints, with one concerned parent saying that her six-year-old child had wanted to use a hairdryer to blow bubbles after seeing the ad, which depicts mermaids showing off their credit card purchases. The ITC ruled that the ad had potentially fatal consequences for children.
Meanwhile, a Russell Hobbs Juicelady ad, which claimed the juice could provide the recommended daily five portions of fruit and vegetables, was ruled to be contrary to Department of Health guidelines. The ad has been banned until the claims are changed.
The body has also banned an Action Man ad, which shows the figurine wielding a sword and severing the arm of an opponent, from appearing before the watershed. The ad for Action Man Samurai Mission uses human and animated characters and was excessively violent, according to the ITC.
In other rulings, NTL has been told it must amend an ad which offered subscribers a chance to watch Premiership Plus football matches for £1. It transpired that subscribers inherited by NTL after it acquired other cable companies had to pay £3.
And an ad for the Ready Steady Cook Popcorn Maker, which claimed to make "real popcorn in seconds", has had to be amended to "real popcorn in minutes", after it failed to justify the claim.
Separately, the Advertising Standards Authority has rejected 13 complaints about three Ryanair press ads featuring Saddam Hussein and slogans such as "Fares falling faster than Saddam!"
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