A Virgin Mobile advert that showed a lavatory attendant holding a man's penis while he urinated has been cleared by the advertising watchdog despite attracting 427 complaints.

The chorus of protest is the largest number of complaints Ofcom has rejected about a single advert since the regulator was established at the end of last year.

Campaigns for Mr Kipling's mince pies and Wrigley's Excite chewing gum, which attracted a larger number of complaints, were banned by Ofcom.

The watchdog said the Virgin Mobile advert was "a light-hearted demonstration of the extreme lengths a service provider would go to provide good service".

"We think that most people would accept it in the spirit that it was intended and not find it unacceptable after 9pm." The campaign, by advertising agency Rainey Kelly Campbell Roalfe/Y&R, showed a young man standing at a urinal when he is approached by an attendant.

The men were filmed from the waist up and the attendant appears to hold the other man's penis while he urinates.

The man then goes into a cubicle, followed by the attendant holding a roll of toilet tissue.

Viewers' objections included the claims that the advert was disgusting, that it showed indecent assault, that the advert denigrated disabled people and their carers and that the advert was offensive because both men were black.

Rainey Kelly Campbell Roalfe/Y&R said the advert had no sexual implications and that Virgin always showed a wide cross-section of the British population in its advertising.

Ofcom said the advert had a "ludicrous and bizarre scenario" and since it was being shown only after 9pm, did not breach the code.

Ofcom also cleared a shocking road safety advert that showed a woman being thrown violently around a pub, receiving terrible injuries, as if she had been hit by an invisible car.

Leo Burnett, the agency that produced the anti-drink drive campaign for the Department of Transport, said its previous anti-drink driving campaign had not influenced viewers.

It said its research had shown the need for the ads to be as realistic and hard-hitting as possible. Without it people did not recognise themselves in the advertising and did not believe it was relevant to them.

The agency said research showed the advert had caused people to question their drinking behaviour.

Ofcom said the advert's powerful images had a serious and legitimate purpose and did not breach the advertising code.

Previously Ofcom inherited an adjudication from the Independent Television Commission about Mr Kipling's mince pies that attracted 797 complaints.

The advert showed a woman giving birth on stage in a nativity play. Ofcom found the advert was in breach of the code but Mr Kipling's had already withdrawn it.

In 2003 the ITC received a record 860 complaints about an advert for Wrigley's Excite brand of chewing gum. That advert showed a man with bad breath apparently coughing up a dog. The ITC banned the advert.

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