For international statesman who have been watching the tragedy of Zimbabwe unfold and kept quiet during its election campaign, everything changes today. Until now, as the campaign progressed, it made sense for Britain, for Zimbabwe's neighbours and for other concerned parties not to express their opinions too forcefully. It would not have helped Morgan Tsvangirai, or the regime's other opponents, if it had seemed that he was being cheered on by Gordon Brown. Indeed, it might have been seen as validation of Mr Mugabe's absurd claim that Zimbabwe's 100,000 per cent inflation rate, and its 80 per cent estimated unemployment, were the consequence of some subterfuge orchestrated in London rather than the result of his regime's policy.

But once the polling stations closed the situation changed dramatically. It is emphatically the obligation of the international community to ensure that the results declared are the accurate representation of the will of the people. It is entirely right that those on whom Zimbabwe might depend economically and politically, and for its moral legitimacy, are intimately involved in the assessment of this election. There is every reason to conclude that this count will be freer and fairer the higher Mr Mugabe calculates the price of stealing it to be. Now is not the time to be shy.

It will apparently be “some days” before the results of the Zimbabwean elections are officially available. This alone is the cause of concern and suspicion. There is the fear that if Robert Mugabe and Zanu (PF) are awarded victory by an electoral commission which they chose themselves, backed by “independent” observers whom they invited in themselves, that will not be an accurate reflection of the views of the Zimbabwean people. Such a possibility is dismissed, however, by the President who insists that he “could not sleep at night” if he thought that his 28-year hold on power had been extended by vote rigging.

It is for the outside world to ensure that Mr Mugabe's slumbers are not interrupted. This responsibility places a particular burden on two men. The first is Thabo Mbeki, the President of South Africa. His own tenure is due to end next year and one of the least impressive aspects of it has been a reluctance to challenge Mr Mugabe over his many outrageous deeds, preferring instead the comfort zone of solidarity in a liberation struggle that ended years ago. It falls to Mr Mbeki to relay to the rest of Africa whether the results are plausible or whether they are the product of shameless manipulation. He should not duck this task, nor fail to fulfil it honestly.

Beyond Africa, history demands that Britain act likewise. It is for David Miliband, the Foreign Secretary, to have a direct interest in this poll and to speak out to the European Union and the United States as to its merits. If Mr Mugabe does steal this election, then that fraud must be met by much more than mumbles of disapproval. The necessary public and private diplomacy will be a test of Mr Miliband's skill and resolve. We cannot expect him to oversee the vote count, but he can begin to orchestrate and articulate the possibilities of life in a post-Mugabe Zimbabwe. This means beginning to talk with the country's potential partners about the resumption of trade, investment, tourism, educational and cultural exchange in the event of a change of government.

The tragedy of this is that Zimbabwe is a nation of extraordinary potential. It should be among the most prosperous on its continent. In the post-Mugabe era it still could be.