David Cameron withdrew his party’s bipartisan support over the economy yesterday and savaged Gordon Brown’s record at the Treasury as he sought to reassert himself after being pushed to the sidelines by the international banking crisis.

The Conservative leader set out tight limits on the party’s co-operation with the Government, making it clear that the offer of help did not stretch beyond the bailout of banks implemented on Monday. His move came amid unease within his party over the bipartisanship strategy, which began at the Conservative Party conference, when Mr Cameron offered to work together on economic matters “at a time of national difficulty”.

Mr Brown seized the offer and turned it to his advantage, appearing to revel in the crisis unencumbered by opposition, and pushing media coverage of the Conservatives to the margins. Mr Cameron responded with a series of increasingly desperate media opportunities, including visits to two bank and building society headquarters in five days. His aides have admitted to frustration in their quest to secure national media coverage since the beginning of the month.

Speaking to a City audience, Mr Cameron said: “Some people think that this decision to support recapitalisation means that we subscribe to the Government’s entire economic policy and doctrine. Let me make it crystal-clear: we do not.”

He criticised Mr Brown’s stewardship of the Treasury for running a budget deficit during an economic boom, assuming “the good times would last for ever”; and relying on housing, public spending and financial services as the engines of growth. “Any proper consideration of what the policies of the last decade have produced leads us to three simple words: we need change. What’s happened over the last ten years is that Labour has broken our economy, and we must fix it.”

Mr Cameron’s aides suggested that passages in his speech had originally been written for his conference address, but were withdrawn at the time because he wanted then to strike a more consensual tone.

The bipartisanship strategy has been unpopular among some MPs and activists. The decision to adopt a more consensual approach was made in the middle of the Conservative Party conference, after the US Congress voted down President Bush’s $700 billion bailout package, and thrashed out by Mr Cameron, George Osborne and William Hague on the 23rd floor of the Hyatt hotel in Birmingham.

George Osborne, the Shadow Chancellor, said then that “when people are anxious about their jobs, this is not the moment people want to see British politicians having a go at each other”.

Aides openly acknowledge that the terms of the bipartisan offer have now changed, and that the time is right to remind voters of Mr Brown’s role in the past ten years. In a speech on the economy, which appeared to shift the Conservative rhetoric in several areas, Mr Cameron told bankers yesterday that they have a moral responsibility to society, and made a tentative attack on globalisation. He criticised assumptions made by Mr Brown, particularly that global financial integration reduced, rather than increased, risks in the domestic economy.

Yesterday the Conservatives’ economic strategy for the autumn was outlined. Mr Cameron will blame Mr Brown’s “irresponsible” policy failures for people losing their homes, businesses and jobs. His failures, the Tory leader will say, are excessive borrowing from overseas, lack of action on personal debt, and the inability to keep banking credit within responsible limits.

Labour said that the bipartisanship offer had been a stunt. Alan Johnson, a Cabinet member, said: “It is now obvious that the offer of support at this difficult time was an expedient designed to help the Tories through their conference rather than a meaningful attempt to help the British people.

“Cameron was wrong on Northern Rock, wrong on short-selling [of shares], wrong on Bradford & Bingley and wrong on his assessment of the global nature of the financial markets and its impact on our economy.”

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