Responding to two requests from Benin's government, Nigeria's President Bola Tinubu "ordered Nigerian Air Force fighter jets to enter the country and take over the airspace to help dislodge the coup plotters from the National TV and a military camp where they had regrouped," said a statement from his office.

The Beninese government has said it has thwarted an attempted coup.

Nigeria said Benin's foreign ministry had requested "immediate Nigerian air support".

It said the ministry's note had mentioned the "urgency and seriousness of the situation" as well as the need to protect the constitutional order, national institutions and security of the population.

Benin also requested the deployment of Nigerian fighter jets inside its airspace for "surveillance and rapid intervention operations under Benin-led coordination".

And it also asked for the deployment of Nigerian ground forces, "strictly for missions approved by the Beninese Command authority in support of the protection of constitutional institutions and the containment of armed Groups".

Tinubu said his troops had acted within the ambit of the ECOWAS protocol on democracy and good governance.

"They have helped stabilise a neighbouring country," he added in the statement.

Regional bloc ECOWAS said earlier that soldiers from Nigeria, Sierra Leone, Ivory Coast and Ghana were being sent to Benin to help contain a coup attempt.