Labour has been accused of "gagging" critics of Britain's nuclear deterrent as three senior ministers joined calls for a debate on replacing Trident.
The party's annual conference in Manchester opened with a bitter row over the decision to rule out bids by several local parties to force the issue onto the agenda.
Angry campaigners complained the gathering was the last chance for open discussion - with Tony Blair promising a decision on a new generation of nuclear weapons this year.
Their cause was boosted when cabinet colleagues Peter Hain and Hilary Benn backed calls for a wider debate - and a chance for delegates to have their say this week.
Northern Ireland Secretary Mr Hain said "progressive" voters would be lost if the Government tried to impose a decision reached by "a couple of cabinet ministers" behind closed doors.
Mr Benn, the International Development Secretary, said there should be a debate "in conference, in the party, in the country and in Parliament".
They were joined by Harriet Harman - like Mr Hain a declared candidate to be Labour's next deputy leader - who warned all taxpayers would want a say on how £25 billion of their money was spent.
Trident dominated the opening of the annual gathering after the conference arrangements committee declared that all 17 motions submitted were inadmissible on technical grounds.
One delegate angrily protested: "We are being gagged. We are not being allowed to move the motions many constituency Labour parties wish to move."
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Another added: "It's our only chance and it is democratic for us to have the opportunity to debate here, especially on such a lifetime decision - an important decision that will affect the security of all of us."
