The cabinet, meeting in Birmingham, has rallied behind Gordon Brown in a public show of support. But some ministers warned privately that they would "review" his position if he failed to transform Labour's prospects.
As the Cabinet held its first meeting since the summer, Jack Straw, its elder statesman, insisted Mr Brown was "secure" but ministers stopped short of declaring he would lead Labour into the next general election.
Some believe that a consensus in the Cabinet may emerge in November to urge him to stand down if he fails to improve his Government's performance by then. His critical hurdles include Labour's annual conference, the pre-Budget report and a difficult by-election in Glenrothes, Fife.
Some of the strongest words of support came from the Foreign Secretary David Miliband, who angered the Brown camp in July by setting out his stall as a future Labour leader.
With all eyes on him yesterday, he had little alternative but to paint a much more positive picture of Labour's prospects. "I am absolutely convinced Gordon can lead us to victory. He has enormous values, drive and vision and I think we are going to prove people wrong," he said.
Writing in The Independent today, Mr Miliband stresses his progressive credentials by calling for a global treaty on the arms trade. "It is bizarre that, while treaties and conventions have existed for several decades to control the spread of nuclear, chemical and biological weapons, there is no equivalent global arrangement to stop weapons flooding into conflict zones," he writes.
Brown allies insisted the Cabinet's mood was "positive" but some ministers appeared to be less effusive in their support. John Hutton, the Business Secretary, said: "We have got to be focused on supporting the work of the Prime Minister, and get behind the work of the Government." Alan Johnson, the Health Secretary, insisted Mr Brown could take the difficult decisions needed to meet the economic challenges facing the country.
One critic claimed: "The Prime Minister has lost the confidence of his Cabinet. But they will not move against him for now, so we are limping on. It's the worst of all worlds – a stalemate."
The Birmingham meeting – the first time the Cabinet has met outside London or Chequers since 1921 – discussed the economy, helping people with housing and fuel costs, this weekend's floods and the crisis in Georgia.
In an email to Labour members, Mr Brown said: "I will not pretend there is a quick fix ... It's about providing support to those who played by the rules but are struggling with rising prices." Drawing a dividing line with the Tories, he said people wanted "a government that is empowering, not overpowering."Reuse content