Margaret Thatcher considered advertising on BBC

Mrs Thatcher took a tour of BBC's Broadcasting House in London in 1980

Margaret Thatcher considered introducing advertising to some BBC radio programmes just a few months after becoming prime minister.

Mrs Thatcher suggested the move in September 1979 when the BBC was running at a deficit of £50m, files released by the National Archives have revealed.

She told then Home Secretary Willie Whitelaw she was "concerned about the extravagance of some... BBC spending".

But by November, Mrs Thatcher had changed her mind.

Prior to that, she had also proposed that a tax could be charged on every new radio sold, with the money used to help finance the BBC, and an amendment so that people would not have to pay the licence fee if they only watched ITV.

'Extremely controversial'

But her proposals did not get universal backing. Bernard Ingham, her press secretary, wrote: "The BBC's reputation worldwide rests in part on its integrity as an independent source of information financed without commercial sponsorship. To introduce commerciality could only, in my view, damage its reputation, particularly in the areas of news and current affairs."

And in a memo to the prime minister, Lord Whitelaw wrote: "I know that there have been suggestions that the BBC should be funded at least in part from advertising.

"This would be extremely controversial and would be bitterly criticised by the BBC Governors and others in the broadcasting world as well as by some people in our party."

By November 1979, a memo to the Home Office suggested Mrs Thatcher had gone off the idea, at least in the short-term.

It read: "The Prime Minister ... has decided that - on reflection - it would be a mistake for the Home Secretary even to raise the possibility of the BBC's accepting radio advertising at this stage" but that "she would not like to rule this out for all time".