Two former Cabinet Ministers have intervened in the Labour leadership contest by suggesting that Gordon Brown has no automatic right to become the next Prime Minister. Alan Milburn, the Blairite former Health Secretary, and Charles Clarke, the former Home Secretary, sent an e-mail to all Labour MPs and peers last night, inviting them to break their silence over the succession.

The pair believe that there is an “enormous appetite” for debate among Labour politicians about the direction of the party, and that MPs should be openly discussing who should take over from Tony Blair.

The e-mail was sent hours after a Times survey found that MPs were privately expressing a marked lack of enthusiasm at the prospect of Mr Brown taking over, although there was no agreement among them on an alternative candidate to challenge the Chancellor.

However, more than a third of those who gave their views — both critics and supporters of the Chancellor — told The Times that they want a “proper” leadership election, with a challenger of Cabinet rank.

Mr Milburn and Mr Clarke have taken the high-risk option of calling a meeting tomorrow morning at the City Inn Hotel in Westminster, underneath Milbank tower, “to develop an open process for ideas and views to be aired”.

So far only two leftwingers, Michael Meacher, the former Environment Secretary, and John McDonnell, another back-bench MP, have declared an interest in running. David Miliband, whom many Blairites wanted to stand, has been urged repeatedly to run by ministerial colleagues but has so far declined.

The e-mail, sent at 8.30pm last night by Mr Milburn, was sent to almost all Labour MPs, including Mr Brown and Mr Miliband but excluding the Prime Minister. It suggested that the process to choose a Labour leader had failed to spark a sufficiently open debate. “After ten years in office we will need to demonstrate that we have the vision and the policies to successfully meet the future challenges faced by our country and the wider world. Like many others in the PLP [Parliamentary Labour Party] and the wider party we believe that requires an open participatory debate,” it said.

“There are some welcome signs that the debate is beginning to happen within Government, in various think-tanks and in contributions made by a range of colleagues. From our discussions with fellow MPs and party members, however, we believe there is an enormous appetite for the debate to be taken forward and given more focus.”

It called on MPs not to be afraid to speak out against the way the leadership issue was being decided.

“As we all know, the coming months are critical for Labour’s future. There will, of course, be many different points of view about the future direction we should take as a party but we believe the critical thing is to develop an open process for ideas and views to be aired.

“Many colleagues have suggested that such a process would provide the opportunity not just of addressing the party — important though that is — but of engaging with the wider public.”

Mr Milburn is a close friend of Mr Blair and is widely believed to be unhappy with the prospect of a Brown premiership.

Mr Clarke has been critical of both Mr Brown and Mr Blair since leaving the job of Home Secretary. The number of Labour MPs in the leadership race, including Gordon Brown; the others are3 Michael Meacher and John McDonnell

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