The interim authorities said Mr B,azoum and his family planned to reach a waiting vehicle to take him to the outskirts of the capital Niamey.

From there they would be flown to Nigeria aboard "two helicopters belonging to a foreign power," Colonel Major Amadou Abdramane said.

"This plan to destabilise our country was thwarted," Col Maj Abdramane said.

He said the main perpetrators had been arrested and an investigation had been opened by the public prosecutor.

Mr Bazoum has been under house arrest with his wife and son since he was ousted in a coup in July. He has refused to resign.

His party and family members have said he has no access to running water, electricity or fresh goods - a situation condemned by Western allies.

The coup in Niger was one of five that swept across West Africa's central Sahel region over the last three years.

As with elected presidents in neighbouring Mali and Burkina Faso, Mr Bazoum was pushed out in part because of mounting insecurity caused by an Islamist insurgency linked to al Qaida and Islamic State in the region, which the military said it would be better able to contain than a civilian government.

In the wake of the July coup, French President Emmanuel Macron announced France was ending its military presence in the country after French troops were also ousted in Mali and Burkina Faso, which have both seen a surge in attacks.

The US has formally declared Mr Bazoum's ousting was a coup and suspended hundreds of millions of dollars in aid, along with military assistance and training.