Buhari also praised outgoing President Goodluck Jonathan as a “worthy opponent” who peacefully relinquished power.
Gen. Buhari beat Jonathan by 15.4 million votes to 12.9 million.
Observers have generally praised the election, though there have been allegations of fraud.
Buhari, of the All Progressives Congress (APC), has become the first opposition candidate to win a presidential election in Nigeria.
The former military ruler in a victory speech on Wednesday described his win as “historic.” He said that the vote had vindicated the people’s belief in democracy.
He also praised President Jonathan as “a worthy opponent” and said that he was extending “the hand of fellowship” to him.
This is a hugely significant moment in Nigeria’s turbulent history. Never before has a sitting president been defeated in an election.
Since independence from Britain in 1960, there have been numerous coups and although the 2011 vote was an improvement, most elections have been rigged or even annulled by the military.
Of course in a relatively close election, there will be millions of people who are not pleased with the outcome. But the whole process is a sign that democracy is deepening in Nigeria and may be a tonic to other countries in Africa.
Nigerians can start to believe that it is possible to remove politicians through the ballot box.
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