The BBC was bracing for a storm of protest today after its governing body decided not to take any further action against Jonathan Ross over obscene phone calls made to the actor Andrew Sachs.

Reporting on the row, the BBC Trust said that the material broadcast on Russell Brand’s Radio 2 show last month was a “deplorable intrusion” into the private lives of Sachs and his granddaughter, Georgina Baillie.

It also said that there was no “editorial justification” and no “informed consent obtained” for airing the "grossly offensive" messages left on the answerphone of the Fawlty Towers actor.

But the board said that the BBC's top management had handled the crisis appropriately and it was not up to the trustees to meddle in personnel matters. The ruling means that Ross will be allowed to return to his £6 million-a-year job as a BBC presenter when his current period of suspension without pay is up in January.

Brand, 33, who boasted during the broadcast that he had slept with Ms Baillie, has already resigned, as has Lesley Douglas, the Radio 2 Controller.

Sir Michael Lyons, chairman of the Trust, said: “We have underlined very clearly that it is not the job of the Trust to make decisions about the terms and conditions of performers or the sanctions that are applied to them when they are found to be wanting. We are very clear that the Director-General has taken the right action with respect to Jonathan Ross.”

He added that the Trust could see nothing new in the evidence about the phone calls: “The common issue is not who the performers are. The common issue is editorial failings...the failings here are in the role of the BBC as the publisher of the material.”

Sir Michael said that the material in the case of Brand’s BBC2 show should not have been recorded and that in all the cases the Trust considered today it could have been excised before broadcast.

He said: “The failings we have discussed this morning are serious but they are being addressed." The BBC “needs to learn some lessons” but usually got it right, he added.

The controversy prompted no less than 42,000 complaints to the BBC, although only two listeners thought to complain after the original broadcast.

The BBC's critics say that senior managers were too slow to respond to the public outrage.

They include David Davies, Tory MP for Monmouthshire, who was quoted as saying today: "The BBC is pathetic for not sacking Jonathan Ross. It is a slap in the face to the licence payers to let him stay on.

"If Jonathan Ross thinks he's worth £6million, let him get it from somewhere else, where people think it is funny to verbally abuse pensioners."

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