Gordon Brown has backed away from a suggestion by Lord Mandelson that he would take part in a US-style, live television debate with David Cameron during the next election.

Earlier today the Business Secretary appeared to have committed the Prime Minister to a television duel with the leader of the Opposition, claiming that Mr Brown “would not have a problem with that”.

WIthin the hour, however, Downing St was throwing cold water on the story. The Prime Minister’s political spokesman insisted that Mr Brown had not dropped his opposition to going to head to head with Mr Cameron during the campaign next year.

In the past the Prime Minister has always parried questions about whether he is prepared to take part in a set piece debate similar to those held during US presidential elections. Tony Blair also repeatedly refused such demands, on the grounds that voters were able to compare party leaders each week at Prime Minister’s Questions.

Asked about the prospect in an interview with the Evening Standard today, however, Lord Mandelson replied: "I don’t think Gordon would have a problem with that.

"While Cameron is good with words, he doesn’t have the ideas or policies to back them. I think people would see through the smile.

"The more the public sees of them, the more they’d realise that Gordon is the man with the substance."

But Mr Brown’s political spokesman said: “The position hasn’t changed. Voters have the chance to compare the party leaders each week at Prime Minister’s Questions.”

Mr Cameron repeated that he was prepared to put himself forward for the debates ealier this month, pointing out that he had debated with David Davis on live TV during the 2005 Tory leadership contest.

The Business Secretary’s interview is the latest of a series he has given since Mr Brown left for a summer break at the beginning of the week.

Yesterday he acknowledged that most people thought Labour would lose. "Of course it's difficult, and of course we're coming from behind. We are the underdogs in politics now," he told Newsnight.

"It's going to be harder for us in other words to be insurgents rather than simply incumbents. It's going to be harder for us to convince people in the way that we need to do that we are going to continue to be, as I say, the changemakers in British politics."

He added: "In my very strong view, the action that Gordon Brown took - very bold, very decisive - last Autumn in his intervention to save the banks and the action that President Obama subsequently took when he came into office in January has literally saved the world economy from a very great and deep recession.

"When the time comes not necessarily to be tested by these events but to be judged by the results of our policies, I think that you'll find that Gordon Brown and his government will be thoroughly vindicated."

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