David Cameron pinned the blame for Britain's economic crisis on Gordon Brown yesterday as his party countered Labour's claims about who was best placed to guide the country through troubled times.

Faced with polls showing that Labour has eaten slightly into the Tory lead, Mr Cameron opened his party's conference by ridiculing Mr Brown's ten-year stewardship of the economy. He told delegates in Birmingham that Mr Brown had had his boom, but that his reputation was now bust.

“We have to ask the question, who brought us and our economy to this position? Who was it that spent and spent and borrowed and borrowed and gave us that massive Budget deficit? Who was it who said that he, and he alone, had rewritten the laws of economics to end boom and bust? The answer is our Prime Minister, the then Chancellor, Gordon Brown.”

Mr Cameron and other Tory chiefs will use their conference to emphasise to the party and country that, if elected, the Conservatives would inherit difficult economic circumstances. In a BBC interview he again refused to rule out the possibility that taxes might have to rise.

Their pitch will be that by tackling debt the Conservatives would never allow such a crisis to happen again. They believe they have to puncture what they see as the myth that the Brown chancellorship was a success.

Under plans to be announced today by George Osborne, the Shadow Chancellor, a new independent office of budget responsibility would issue regular reports on whether the Government was reducing the budget and paying back national debt, and the Bank of England would have greater power to tell banks to cut their lending. The Conservatives have recruited Mr Brown's former City envoy, Sir James Sassoon, to help to prepare an overhaul of financial regulation.

Mr Cameron hit out at those who have been “bashing” bankers for causing global financial turmoil. He said that he would not seek cheap headlines by blaming greedy City practices for the crisis, but he also said that the Tories would not sign blank cheques for the taxpayer to bail out failing institutions. “What you won't hear from me this week is the sort of easy, cheap lines beating up on the market system, bashing financiers,” he told BBC1's Andrew Marr Show. “It might get you some easy headlines, but it is not going to pay a single mortgage, it is not going to save a single job.

“I think that we have had a failure of regulation and we have had a debt boom that went on for far too long and it reached into parts of the economy it should not have done.” Asked if he could rule out tax increases, Mr Cameron said: “If we win the election, we are clearly going to face an extremely tough time. No responsible Opposition can ever rule things out. Of course I can't rule that out.”

Mr Cameron said that he stood by his pledge to stick to the Government's spending plans to 2011, but that recent spending pledges by Gordon Brown meant that the Prime Minister may not be able to keep to his own “realistic and tight” limit of about 2 per cent annual growth in the Budget.

Other ideas set out in the Tory economic reconstruction plan include a fuel duty stabiliser to help to even out the effects of rising oil prices.

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