Senegal opposition presidential candidate Bassirou Diomaye Faye, a political newcomer popular among disaffected youth, promised on Monday to govern with humility and transparency.

Faye, set to be declared the next president after his main rival called him to concede defeat, thanked President Macky Sall and other candidates for respecting Senegal's democratic tradition by recognising his victory well before official results.

"In electing me, the Senegalese people have decided on a break with a past," Faye told journalists in his first public appearance since the election. "I promise to govern with humility and transparency."

Provisional results showed Faye with about 53.7% and Amadou Ba - from the current ruling coalition - with 36.2% based on tallies from 90% of polling stations in the first-round vote, the electoral commission said.

Ba and Sall both congratulated Faye, who turned 44 on Monday. They hailed the outcome as a win for Senegal, whose reputation as one of West Africa's most stable democracies took a hit when Sall postponed the vote.

"The Senegalese people have reinforced the good health of our democracy.. I wish him (Faye) success at the head of our country," Ba said.

A peaceful transition of power in Senegal would mark a boost for democracy in West Africa, where there have been eight military coups since 2020.

Some of the juntas that seized power have cut ties with traditional regional power-brokers such as France and the US, turning instead to Russia for help in their fight against a jihadist insurgency spreading through countries that neighbour Senegal.

Senegal's international bonds rose on reports that Faye was close to being declared a winner, reversing sharp falls from earlier in the day.

Many hope the vote will bring stability and an economic boost after three years of unprecedented political turbulence and several waves of deadly anti-government protests.

"I am happy to see there is a wind of change," said an opposition supporter named Tall, who joined revellers during the night as street celebrations broke out in anticipation of Faye's victory.

"It is wonderful because democracy has won. Many thought it would not happen," he said, giving only his first name.

Full, official results are expected to be announced by the Dakar appeals court on Friday.

YOUNG VOTERS

Faye owes much of his success to the backing of firebrand opposition leader Ousmane Sonko, who was barred from running due to a defamation conviction.

The two former tax inspectors, who were both released from jail this month, campaigned together under the slogan "Diomaye is Sonko", promising to fight corruption and prioritise national economic interests.

They are particularly popular among young voters in a country where more than 60% of people are under 25 and struggle to find jobs. Faye promised to dedicate more state resources to help the youths.

Police crackdowns on protests buoyed the opposition, as did rising living costs and concerns Sall would seek to extend his mandate beyond constitutional limits.

Anger around Sonko's prosecution grew when authorities sought to postpone by 10 months the vote, initially scheduled for February.

Investors were wary about whether a new government would be less business friendly than Sall's government, which attracted investments into infrastructure.

Senegal is set to start producing oil and gas this year, and Faye has promised a raft of changes including plans to renegotiate oil and gas contracts. Still, he sought to reassure investors last week the country would respect its commitments.