Adama Barrow greets supporters during a gathering in the buffer Zone district of Talinding in November
Electoral commission chief Alieu Momarr Njai declared on state TV that Mr Jammeh had lost and had recorded a statement to concede, which would be broadcast later.
He said Mr Jammeh received just 36.7 per cent of the vote compared to Adama Barrow’s 45.5 per cent.
“Having received 263, 515 votes out of the total votes cast in the election, I hereby declare Adama Barrow newly elected to serve as president of the republic of the Gambia,” said Mr Njai.
Earlier he said it was “very unique” for Mr Jammeh to be conceding, more than two decades after he seized power from Gambia’s first president in a bloodless coup.
Mr Barrow, Jammeh’s opponent who managed to unify eight different opposition parties behind him, said he was expecting a congratulatory phone call from the president.
Mr Barrow once worked as a security guard at a branch of Argos in London before becoming a businessman in his home country. He campaigned as a reformer who would reverse Mr Jammeh’s decision to withdraw Gambia from the International Criminal Court.
Gambia’s 900,000 registered voters faced a total internet blackout during Thursday’s vote, and international phone lines were also cut.
But the internet appeared to have been restored on Friday afternoon as the result became clear, and activists and journalists flocked to social media to declare victory for Mr Barrow.
The result came as a shock after months of campaigning in which Mr Jammeh had used state resources and media to advance his own cause, while the authorities clamped down on opposition activities.
Earlier this week Mr Jammeh said that his “presidency and power are in the hands of Allah and only Allah can take it from me”. During the campaign, he said that “being called a dictator doesn’t bother me at all, because I am a dictator of development and progress”.
But Mr Barrow said on voting day that he strongly believed Gambians were ready for change, adding: “He is not going to be re-elected – his era is finished.”
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