Sir Alan Sugar’s appointment to Gordon Brown’s government was under siege today after the Tories said that he needed to chose between his television career and role advising Labour.

The star of the BBC show The Apprentice — which comes to a climax tonight — insisted that there was nothing political in his decision to accept a role advising Gordon Brown.

“I don’t see this as kind of a political thing. I know that everybody else does,” he told the BBC.

“As far as I’m concerned I’ve just got a passion to help out young people, to help out businesses and act as a kind of giant’s Dragon Den if you like… although not with my money."

But critics pointed out that his decision to accept a Labour peerage as well as the advisory position made it harder to continue with BBC role. He also hinted he might not have time to be a regular attendee in the Lords, despite new guidelines that peers should be “willing to commit the time necessary to make an effective contribution to the House of Lords”.

Sir Michael Lyons, the chair of the BBC Trust, will now be asked to explain the appointment and Sir Alan faces a crunch meeting with BBC executives this week. Despite briefings from Sir Alan’s PR company, the BBC stressed today that a final decision had not been made about the future of the show.

Sir Alan, who has made his millions in computers and property, is also rumoured to be being considered as a candidate as the Labour candidate for London mayor in 2012. He has been a member of the Prime Minister’s business council since it launched.

The Conservatives today launched a concerted attempt to scupper the appointment.

Jeremy Hunt, Shadow Culture, Media and Sport Secretary, said: “Presenting a programme for the BBC and working for the Government on the same issue is totally incompatible with the BBC’s rules on political independence and impartiality. Sir Alan Sugar needs to make a choice between his role in The Apprentice and his role as the Government’s business tsar.

“I have written to Sir Michael Lyons and asked him as a matter of urgency to explain who at the BBC gave guidance to Sir Alan and whether he had informed them that he would be a Labour peer.”

John Whittingdale, chair of the Culture Select committee of MPs, said: “In my view it is not possible for him to continue to present The Apprentice at the same time as he is so closely identified with the Government.

“I had assumed that by accepting the role as Enterprise Czar he would stand down from his role in The Apprentice.

“His show is all about business and enterprise. He will be making recommendations on policy to Government. He is already a political figure – he has made no secret of his admiration for Gordon Brown.

“Either he is an influential figure in Government or this is just window dressing.”

Sir Alan told the BBC that his role would not involve policy making.

"It’s very simple: all I am is an adviser. I’m not a policymaker, you know, and I’m just going to take a look at some of the things that the government and the civil service do to try and help business and advise.”

He added he saw his role as politically neutral. “I’ve never met Mr Cameron and I don’t know anything about him really.” In 1992, Sir Alan said the same thing about Gordon Brown, yet within six years had become an ally.

Sir Alan will meet with senior BBC executives this week to discuss the role in depth.

A BBC source stressed the situation was very different to when Melvyn Bragg was forced to hand over the job of presenting Radio 4’s 'Start the Week' because of a Labour peerage.

The source said that 'Start the Week' involved political discussions and therefore was incompatible with the peerage. However Lord Bragg’s subsequent radio show, 'In Our Time', which discusses the history of ideas, was a good example of where a party-political peer can continue working for the corporation.

The BBC was also at pains to point out that Sir Alan is not yet a Labour peer, so there was never any question of last night’s final being axed.

A BBC spokeswoman said: "Sir Alan is in discussion with us about his plans and assured us that he is determined not to do anything that would jeopardise his work at the BBC which is something he greatly values."

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