Ofcom chief executive Ed Richards said it would be "foolish" to commit to a date when the UK's analogue radio signals will be switched off, until more consideration is given to the matter.

Speaking at the Cambridge Radio Festival, Richards said more work need to be done in considering when such a move would be in the interests of the industry and the listeners.

Richards said: "I am not going to hoodwink anyone into thinking this is an easy task, and it would be foolish of me to do. We have to work it through....I have no reticence about it, but I want to engage with it properly and not with rose-tinted spectacles."

Richards said Ofcom would be likely recommend to the new media secretary James Purnell, that a working group of relevant parties be set up to consider the implications of analogue switch off.

Ofcom has so far recommended there be a review of AM transmissions in 2009, and in FM transmissions in 2012.