BBC Radio 2 controller Lesley Douglas today resigned in the wake of the Russell Brand and Jonathan Ross phone prank affair, saying she took responsibility for the events of the last two weeks, which she said had happened "on my watch".

Ross has been suspended from all BBC TV and radio services without pay for 12 weeks over his part in the prank calls to actor Andrew Sachs.

Mark Thompson, the BBC director general, said the contribution of the corporation's highest paid star to the "Sachsgate" prank calls "was utterly unacceptable and cannot be allowed to go uncensured or without sanction".

The BBC Trust also issued a statement expressing its "dismay" over the "deplorable intrusion" into the privacy of Andrew Sachs and his granddaughter and has ordered that an apology to licence fee payers must be broadcast on Radio 2.

Douglas, in a letter to Thompson, said: "The last week has been a painful one for the BBC and particularly for BBC Radio 2.

"The events of the last two weeks happened on my watch. I believe it is right that I take responsibility for what has happened.

"It is a matter of the greatest possible sadness to me that a programme on my network has been the cause of such a controversy.

"I would like to take this opportunity to offer my personal apology to Andrew Sachs and his family and to the audience for what has happened."

A statement released by BBC management said: "The presenter Jonathan Ross will be suspended from all broadcasting for the BBC for a 12-week period, ending in mid-January 2009.

"He will not be paid by the BBC during this period: the fees that would have been paid will be deducted from his BBC contract."

Thompson said: "The ultimate editorial responsibility for BBC programmes lies with producers and editorial managers. The consequences of errors of judgement are therefore more serious for managers.

"Nonetheless, Jonathan Ross's contribution to this edition of the Russell Brand show was utterly unacceptable and cannot be allowed to go uncensured or without sanction.

"A 12-week suspension is an exceptional step, but I believe it is a proportionate response to Jonathan's role in this unhappy affair.

Douglas said her decision to resign was "my decision alone". She will step down as controller of BBC Radio 2, BBC 6Music and from her role as controller of popular music.

She added: "It has been a huge privilege to have been entrusted with the leadership of the UK's most popular radio station, which is so intensely loved by the audience.

"I have also had the tremendous pleasure of launching BBC 6 Music and more recently of leading popular music output across the BBC.

"I know I leave BBC Radio 2 and 6 Music in the hands of a dedicated and passionate team of incredibly talented presenters and production staff. I am enormously proud of what we have achieved together."

Thompson said he accepted Douglas's decision to resign with "real sadness".

"There is no doubt that my sadness today will be shared both across the BBC and the wider music industry," said Thompson in a letter accepting Douglas's decision.

"You have been an outstanding head of programmes and then Controller of Radio 2 over the past eight years.

"You have presided over a creative transformation of the network, and have rightly been recognised by the industry for your massive contribution to UK radio.

"Your decision to take responsibility for what has happened is an illustration of the integrity and commitment which has characterised your leadership at BBC Radio 2 and BBC 6 Music.

"Over the past 23 years, you have been a devoted servant of the BBC, and your absence will be felt by your many colleagues and friends at the BBC.

"I am sure you will continue to make an outstanding contribution to radio and popular music in the UK."

The BBC Trust said: "The trust is dismayed both that the offensive comments broadcast on the Russell Brand Show on October 18 fell so far short of audiences' legitimate expectations, and by the deplorable intrusion in to the privacy of Mr Sachs and his granddaughter.

"The transmission of these comments via a BBC radio programme represents an abuse of the privilege given to the BBC to broadcast to its audiences. On behalf of the BBC, the trust offers a full and unreserved apology to Andrew Sachs, Georgina Baillie and the rest of his family. The trust extends this apology to licence fee payers as a whole.

"The trust has required the executive to issue an on-air apology to licence fee payers on BBC Radio 2 for the serious and deliberate breaches of the BBC editorial guidelines on offence and privacy. The form and timing of the apology will be agreed by the trust's committee. We have also required the director general to write personally to Andrew Sachs and Georgina Baillie to apologise on behalf of the corporation."

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