PORTO-NOVO - Benin's outgoing Prime Minister Lionel Zinsou has conceded defeat to businessman Patrice Talon in Sunday's presidential run-off.
Mr Zinsou posted on Facebook that he had called Mr Talon to congratulate him "on his victory and wish him luck".
President Thomas Boni Yayi is stepping down after two terms.
Mr Talon, known as the "king of cotton", used to be his close ally but was accused of masterminding a plot to poison him in 2012.
The electoral commission is expected to announce provisional results later on Monday.
"The provisional results point to a decisive victory for Patrice Talon," Mr Zinsou told the AFP news agency by telephone.
"The difference is significant, electoral victory is certain."
This is a turnaround from the first round vote last month when Mr Talon came slightly behind Mr Zinsou with 25% compared to his 28%.
The West African nation introduced multi-party democracy in 1990 after nearly two decades of military rule - the first to do so in sub-Saharan Africa.