Before Prime Minister Tony Blair could even open his mouth to reveal the secrets of Britain's biggest mystery, the public spat between the minister in charge of the Dome project, Peter Mandelson, and its former creative director Stephen Bayley re-ignited on the airwaves.

Mr Mandelson and Mr Bayley were interviewed separately on BBC Radio 4's Today programme.

Mr Bayley, who resigned last month, said: "Peter Mandelson tends to dismiss all criticism about the Millennium Dome.

"He will say that all great national projects like the Great Exhibition and the Festival of Britain attracted their critics and, of course, he is right.

"But the difference is that in 1851 and 1951 the philistines were on the outside, today I'm afraid the philistines are on the inside.

"I do think there's a problem with the quality of the contents."

Mr Bayley said he was an enthusiast for the whole project, but quit because of the way its creative element was being directed.

"I found myself in a state of continuous frustration. I do think a project like this does need strong creative direction ... any creative activity needs one person making decisions.

"I'm afraid the management of the Millennium is civil servants - civil servants who are liable to interference from their political bosses.

"I'm afraid the very same thing that makes the British civil servant excellent and incorruptible also disqualifies the British civil service from running creative projects. They won't make risky decisions."

Mr Bayley also said there was something "troubling" about the style of the politics involved in the project.

"You can't have decisions tested by focus groups, you can't keep on asking the public `What do you want, we will give it to you'.

"You have to take brave, imaginative leaps and offer the public things they can't even imagine."

Mr Bayley said the Dome's proposed contents appeared to be of variable quality and singled out the controversial Mother and Child figures. He said: "Some parts of it are absolutely excellent. There are parts of the contents of the Millennium Dome designed by architects of world class.

"There are other parts which don't reach the standards of excellence which I would say is appropriate to a major and extremely expensive venture like this.

"The figure of the mother and child. I personally feel that is straightforward - It's bad art. It's a dated idea."

Mr Mandelson, however, insisted that the Dome was destined to be a great success and denied it was a re-election stunt by the Labour Government.

"What we have got is very, very good content being constructed by the best designers, not only in Britain but amongst the best designers in the world," he said.

"It's going to meet a very, very high test indeed and I believe it's going to pass with flying colours."

Like the Prime Minister who has called for an end to "carping" about the Dome, Mr Mandelson urged against the levelling of "ritualistic" criticisms and stoutly defended the project's management.

"The Millennium Experience is being organised on the basis of a company - and I am only the shareholder - it has a chief executive, it has excellent senior management, it has a board, it has an executive committee, all of whom are drawn from different parts of the creative and entertainment business, individuals who have an enormous amount of experience and expertise which they are giving free to Britain's Millennium celebration and the creation of this Dome," he said.

Mr Mandelson was dismissive of Mr Bayley's criticisms, saying: "I gather he was referring to himself as the sort of hysterical prima donna megalomaniac the Millennium Experience needs in order to sort itself out.

"Well frankly we've had enough experience of that and we don't need any more."