One member of the Shadow Cabinet said Mr Brown was 'too conservative'. Criticism of the Labour leadership for its conservatism is extending across the whole range of policy, including the monarchy and the constitution.
A poll of 100 Labour MPs showed a majority supported radical reform of the monarchy. In spite of the leadership's concern at the outspoken calls by Mo Mowlam and Jack Straw for the monarchy to be reformed, the poll by the Sunday Telegraph showed 32 per cent of the MPs who replied supported the reforms, and 24 per cent wanted a republic.
The change of mood in favour of reform will put pressure on the constitutional commission chaired by Tony Blair, a leading advocate of modernisation by Labour, to support changes to the Royal Prerogative.
But Shadow Cabinet members believe the debate about the monarchy is a side-issue compared to the party's need to adopt a more radical agenda.
One source described the windfall profits tax on the privatised utilities by Mr Brown and John Smith, the Labour leader, as 'a cop out', although it was attacked in the Commons by John Major. John Prescott, who has developed a radical agenda as the party's spokesman on transport, said on the ITV Walden programme that Labour had run away from change. Although Mr Prescott is a traditionalist, who opposed cutting the party's links with the unions, he said Labour had to consider targeting welfare benefits and pensions.
Tribunite MPs on the 'soft left' of the party and some of Mr Smith's Shadow Cabinet colleagues are demanding more explicit promises of higher spending by Labour at the next election, with higher taxation if necessary, in spite of the evidence that such a policy helped Labour lose the last election.
'Gordon is too Conservative. The windfall tax was a cop-out from actually considering macro- economic solutions. At the last election, we were fighting it on the basis that we stuck to the Government's spending levels.
'Gordon seems to be talking about fighting the next election in the same way. He still seems to be accepting the Government's spending plans as the limit for our ambitions. We need more far reaching proposals to get the economy going again,' one Labour front bench source said.