The organisation of an Olympics is a marathon and not a sprint. Despite that, certain commentators and professional whingers are treating London’s plans for the 2012 Games as if they represented a set of impossibly high hurdles. Tessa Jowell, the Culture Secretary, informed MPs yesterday that the expense on stadiums and the village, for which the Olympic Delivery Authority is responsible, is now estimated to be £900 million higher than originally expected. It may not be the last revision to these numbers. The public, and Londoners especially, need to be realistic about the flukiness of forecasts.

The Olympics are an extraordinary sporting event and should be approached in that spirit. They are a once-in-a-century opportunity. Facilities that would otherwise never have made it beyond the drawing board will be built, a major regeneration programme in a capital city that desperately requires the extra space will actually happen, and other advantages ranging from increased tourism to the prospect of healthier young people are genuine. There will be many events on offer in less than six years’ time. There would be no logic in making either bean-counting or cynicism an official sport at this stage of the process. What matters is that the Games are a triumph for London and Britain and that the expenditure on them does not spiral out of control.

There is no reason to be discouraged on either of these counts. London’s activities have been the subject of intensive monitoring by the International Olympic Committee from the moment that the contracts were signed in Singapore last July; those inspectors and observers are not merely satisfied, but delighted with the progress that they have witnessed. London is believed to be two years ahead of Sydney at the same time in the organising cycle and even farther ahead of Athens. The quality of the people and companies who have been hired is impressive. The fundamentals of this Olympics are sound and there is every reason to be confident that the Games will occur on time and with real style.

Whether they will be on budget is, inevitably, more debatable. It should not be forgotten that the opening numbers would have made the 2012 Games an exceptional bargain. What needs to be done now is for the Treasury to agree to set aside a dedicated sum which the Department for Culture, Media and Sport and its various offshoots can utilise. The current expected cost to London council taxpayers — £20 a year over 12 years or 38p a week — is far from being an out-rageous sum of money. The idea of London’s residents being “bankrupted” by the 2012 Olympics is a grotesque exaggeration perpetuated by killjoys who relish misery and cherish pessimism..

The expense faced by the citizens of the capital would, in any case, be minimised if the drive for sponsorship nets the returns available. The receipts from the major international sponsors, such as overseas television networks and familiar global brands, can be estimated with some confidence. What is less predictable is the amount that will be obtained in backing from within the United Kingdom. There is the risk that needless negativity at an early moment in proceedings will discourage local sponsors from coming forward. It would be a tragedy if British business did not share in the glory of London’s Games. Ministers are right to be candid about the costs of this enterprise. They should be no less bold in extolling the benefits of a great event and in neutering the naysayers.