Published: 24 April 2007

Umaru Yar'Adua was declared the winner of Nigeria's presidential election yesterday, defeating his opponents - if the figures are to be believed - by a margin of four to one. Amid widespread condemnation from election observers, local and foreign, and demands that the election is run again, all the opposition parties have rejected the result.

Max Van den Berg, the mission head of the European Union monitors, said the poll "had fallen far short of basic international and regional standards for democratic elections".

Mr Yar'Adua, the hand-picked successor of President Olusegun Obasanjo, who must step down after two terms on 29 May, was backed by the ruling Peoples Democratic Party (PDP), as well as the police, army and most of Nigeria's state and local governments

The opposition say PDP supporters were deployed to ensure that the ballot boxes were full of PDP votes one way or another. They set about it with brazen vigour, stealing and stuffing ballot boxes, intimidating voters, buying votes and bribing officials. Much of this was done in view of observers and journalists. Only in Lagos and Kano, Nigeria's two biggest cities, did they hold off, fearful of a backlash. Both voted against the ruling party.

According to respected Nigerian journalists, Mr Yar'Adua may have won anyway. But the margin of his victory is clearly absurd to independent observers. The final figures may well have been invented.

There is widespread anger over the election, but it is hard to see how ordinary Nigerians can make their voices heard. "Everything now depends on leadership," Pat Utomi, the former head of the Lagos Business School and a presidential candidate, said.

Mr Yar'Adua will clearly suffer from a crisis of legitimacy when he assumes power, but most Nigerians, 71 per cent of whom live on less than a dollar a day, receive nothing directly or indirectly from the country's wealthy government. The elite who own Nigeria will want to cut deals with the new leader. So too, perhaps, will western governments.

Whatever the aftermath of the elections, President Obasanjo will leave office under a cloud. The hopes that he would turn Nigeria around after years of military rule have been dashed. Even the elections in Zimbabwe under Robert Mugabe are seen as fairer than those in Nigeria.

Mr Yar'Adua, a Muslim northerner from an aristocratic family, has a relatively clean reputation and may have been only vaguely aware of what was being done in his name. He has never sought the limelight - indeed there is no evidence that he ever even wanted the presidency.

His older brother, Shehu, was a military man and second in command to Mr Obasanjo when he ruled the country in the late 1970s. Umaru rebelled by joining a socialist movement but then left politics and became a university chemistry teacher. When his brother died in jail in 1997 - almost certainly murdered by the military regime - Umaru returned to politics.

Now 56, he has been governor of the northern Katsina State for the past eight years and Nigerian observers say he is stubborn but does not have a grip of the politics in either his own state or nationally. He was forced by militants to recognise strict Islamic law in Katsina, although he did not implement it and has reassured Nigerians that he respects all religions.

He has travelled little outside Nigeria but has been to Britain. A month ago he was flown to Germany for kidney treatment and appears to have a long-term illness. Many people interpret his weakness as a sign that Mr Obasanjo, whose bid to change the constitution and run for a third term was quashed in the senate, will continue to rule Nigeria indirectly. Others, however, think that Mr Yar'Adua will try to cut the reins and may, in time, even turn on Mr Obasanjo by having him investigated for corruption.