The shelves of Whitehall groan under the weight of policy reviews discarded and plans never enacted. Next Monday a new policy blueprint, Building Britain's Future, will be added to their number. In an interview with The Times today, Gordon Brown sets out his plan for the general election, based on a rapid return to growth and a new wave of public service reform. The Prime Minister also makes it emphatically clear that he has no intention of swelling the ranks of teachers just yet.

Mr Brown's main hope is that economic growth will presage political recovery. The Prime Minister does, indeed, deserve credit for holding his nerve through successive financial and economic crises. The upshot, however, is that the country is now in a severe fiscal crisis, the severity of which seems, from his public utterances, to have eluded him. In 2010 British public sector borrowing will reach £175 billion and we are in a fiscal hole that the Institute for Fiscal Studies has said is worse than the late 1970s. The public debt of 30 years ago was alleviated by the North Sea oil windfall and the impact of inflation. Yet cuts in capital spending, education and local government all followed inexorably.

The same will happen after the general election, whatever the result. In this respect Mr Brown's words to The Times were not encouraging. If he is to gain one last hearing from the British public he needs to give up his claim that he will invest where his opponents would cut. He needs, instead, to start talking about the shape and size of a viable state that falls within the parameters set by the reality of the public finances.

Mr Brown will find, buried under a pile of old newspapers in Whitehall, covered in the dust of neglect, some work that could help him. Tony Blair, late in his premiership, conducted what he called a fundamental savings review. The idea, prophetic as it turned out, was to consider all state spending anew, to force every programme, in effect, to reapply to the taxpayer for funding. The programme was conducted with no enthusiasm in Whitehall and was never published in its intended form. But that is precisely the thinking, charting a clear path through the lean years, that is now required.

Mr Brown could do a lot worse than cite the example of Canada that, in the early 1990s, was running a budget deficit of 9.2 per cent of GDP, much the same as Britain's today. A series of isolated efficiency drives had failed to deal with rising debts. And so, in 1994, a group of ministers oversaw a “programme review” that introduced once-and-for-all cuts that closed down initiatives that did not pass a stringent test.

That basic review of the functions of the State urgently needs to be coupled with a thorough programme of reform to ensure that the smaller State is as efficient as it can be. Just before Mr Brown became Prime Minister the Government published a series of policy reviews that, taken as a group, set out a comprehensive prospectus for reform, premised on the idea that public services needed to be more responsive to the people that they served. Here, perhaps, we can raise one cheer for Building Britain's Future, which Mr Brown claims will herald better powers of redress in the health service, in education and with respect to the police.

The fundamental savings review and the policy programmes define the task for the Prime Minister. It is an onerous task and time is short. Mr Brown hopes that his economic competence will be rewarded with a political dividend. It appears that, at the eleventh hour, he may have come to appreciate the need for a more efficient State. But if he has yet to comprehend the state of the public finances he will still find a public no longer willing to invest in him.