Andrew Sachs would be “horrified” if disgraced comedian Russell Brand had actually slept with his granddaughter, he said today.

Mr Sachs, 78, spoke out as the BBC's senior management faced mounting calls to personally apologise for obscene phone calls made to the Fawlty Towers veteran by Brand and chat show host Jonathan Ross.

Media watchdog Ofcom announced today that it will be investigating the incident.

Russell Brand joked he slept with Andrew Sachs's granddaughter Georgina Baillie, right

The BBC apologised yesterday to Mr Sachs about lewd taunts left on his answering machine by the duo during Brand's Radio 2 show.

They concerned the comedy actor's 23-year-old granddaughter Georgina Baillie, and the presenters joked that he might kill himself as a result of the remarks.

The corporaton is also investigating how the pre-recorded segment went to air on 18 October — to be heard by two million listeners — despite protests from Mr Sachs.

Speaking as he left his home in Kilburn this morning, Mr Sachs confirmed he had replied to a “very nice” letter of apology he received from Ross, 47, who is paid £6m a year by the BBC.

Asked if he had been contacted by Brand, Mr Sachs said he hadn't, adding: “I don't care — he is in enough trouble as it is.”

The BBC has received more than 1,500 complaints about the matter — many demanding that Brand and Ross be taken off-air or sacked — since Mr Sachs was taunted with crude details about Brand, 33, having sex with Miss Baillie.

Mr Sachs said he would be appalled if it were true, adding: “It's not for me to know these things but, of course, I would be horrified.”

The actor, who played waiter Manuel in Fawlty Towers, demanded that Brand and Ross say “sorry” to his granddaughter for their humiliating tirade.

“They apologise to me and they say how awful for Mr Sachs, but nobody has offered any apology to my grand-daughter,” he said.

“I replied to Jonathan Ross and suggested that is where he should direct his attentions.”

But Mr Sachs did not join the calls for the comedy stars to be sacked.

He said: “That's up to some people, I don't want any kind of revenge.”

He said he had not spoken to his granddaughter since the furore erupted because she had been working abroad.

Miss Baillie, who is an erotic dancer and aspiring model, returned from Austria yesterday where she had been performing with her horror-themed burlesque troupe Satanic Sluts Extreme.