Nigeria and Niger have signed a deal to boost their security cooperation, the Nigerian military said on Thursday, despite tensions between the neighbours since a coup in Niger a year ago.

"Both parties reaffirmed their commitment to resuming and strengthening collaboration, with a view to ensuring regional stability and security," a Nigerian military statement said after the signing of a memorandum of understanding by the nations' defence chiefs in Niamey, Niger's capital, on Wednesday.

Ties between the two countries soured after Niger's junta toppled Mohamed Bazoum and the July 2023 coup has also split the Economic Community of West African States (ECOWAS), raising questions about the fight against Islamist violence in the region.

ECOWAS threatened to invade Niger if diplomatic efforts to restore the democratic government failed, prompting Niger, Burkina Faso and Mali to pull out of the 15-country bloc in January.

They said ECOWAS had failed to help them tackle Islamist violence, signing a military agreement to form the Alliance of Sahel States - a parallel body.

Niger has remained in a Nigeria-led multinational joint taskforce fighting Boko Haram in the Lake Chad region, but has kept its activities to a minimum.

Under the deal signed this week, it "reaffirmed its readiness to resume active participation in security cooperation under the Multinational Joint Task Force", the Nigerian statement said.