The two rivals vying to be Benin's next president on Friday kicked off their campaigns for next month's election in which the main opposition party has been barred from standing.

President Patrice Talon, who has served two five-year terms running the West African country, is barred under the constitution from standing again.

But his Finance Minister Romuald Wadagni is a strong favourite to win against opposition candidate Paul Hounkpe in the April 12 polls.

On the first of several planned stops in the north on Friday, Wadagni rallied thousands of supporters at a stadium in the town of Kandi, raising issues of regional development and security.

Northern Benin has been hit by a spillover of attacks by terror groups from neighbouring Burkina Faso and Niger for several years.

Opposition sidelined

Hounkpe, from the FCBE party, opened his electoral campaign in a conference room in the coastal city of Cotonou, where still only a few election posters and placards of the two candidates were seen.

"The game isn't decided yet," declared Hounkpe, to around a hundred supporters.

The main opposition, the Democrats, was sidelined from the polls after failing to gather enough signatures and has said it will not support any candidate.

Several of their senior figures have thrown their support behind Wadagni in recent days.

A deadly coup attempt by army mutineers on December 7 was put down in a matter of hours by the military with support from Nigeria and France.

However, it did not prevent legislative and local elections being held the following month in which Talon's ruling bloc secured a majority in parliament.