Michael Palin has confirmed that the letter from dozens of celebrities urging David Cameron not to “diminish” the BBC was organised by the corporation’s senior executives.

Speaking on the Victoria Derbyshire show on BBC 2, Palin said BBC TV boss Danny Cohen had asked him to sign the letter.

“Danny Cohen rang me up, he just asked ‘Would you sign? The charter is coming up we’re a bit worried the BBC would become smaller and less significant.’”

“I didn’t think that was avery good idea that it should become that much smaller or that it should be sort of chipped away at by special interest groups. Let’s keep the BBC doing what it does best, which is an enormous amount of work.”

His comments follow reports in the Times that Radio 1 presenter Annie Nightingale was asked to sign the letter by the station’s controller, Ben Cooper.

She said: “I bumped into Ben a couple of days ago. He said Danny Cohen [the director of BBC television] was putting this letter together and said, ‘Would you like to be included?’ I said, ‘Yeah’. I understood vaguely what it would say. I didn’t read the letter before it went out.”

"BBC boss Danny Cohen asked me to sign letter supporting BBC" says Michael Palin https://t.co/7cIJZLqZRK — Victoria Derbyshire (@VictoriaLIVE) July 16, 2015

Other stars putting their names to the letter included JK Rowling, Daniel Craig and Chris Evans.

The letter read: “We are writing to place on record at the very start of the process our concern that nothing should be done to diminish the BBC or turn it into a narrowly focused market-failure broadcaster.

“In our view, a diminished BBC would simply mean a diminished Britain.”