West African regional group weighs next steps on Niger

West African leaders are weighing their next moves as they seek to overturn a military coup in Niger that has rocked the region but also triggered a groundswell of support in the country.

Niger's military last month imprisoned President Mohamed Bazoum and assumed power, drawing condemnation from international powers and raising the spectre of further conflict in the impoverished Sahel region of West Africa which is already overrun by a deadly Islamist insurgency.

The regional bloc ECOWAS on Thursday decided to activate a task force drawing on troops from across the region for a possible military intervention to undo what was the seventh coup in West and Central Africa in three years.

At stake is not just the fate of Niger - a major uranium producer and key Western ally in the fight against the Islamists - but also the concerns of global powers with key strategic interests in the semi-desert zone.

United States, French, German and Italian troops are stationed in Niger to repel local affiliates of al Qaeda and Islamic State that have killed thousands and displaced millions across the Sahel.

Western powers fear Russian influence could grow stronger if the junta in Niger follows Mali's example by ejecting Western troops and inviting in mercenaries from Russia's Wagner Group.

Thousands of people gathered in Niger's capital on Friday to demonstrate in favour of the coup.

Popular anger is targeted at former colonial power France, whose forces were kicked out of Mali and Burkina Faso after the coups there and whose presence in Niger is under threat.

The rally began at a French military base in the capital Niamey, then protesters with signs and flags spread onto surrounding streets.

"Long live Russia," one protester's sign read.

"Down with France ... Down with ECOWAS," referring to the Economic Community of West African States.

It was not yet clear how long the ECOWAS force would take to assemble, how big it would be and if it would actually invade.

Regional army chiefs were set to meet in the coming days.

The organisation stressed all options were on the table and it hoped for a peaceful resolution.

Security analysts said the force could take weeks to set up, potentially leaving room for negotiations.

Ivory Coast is the only country so far to specify how many troops it would send, promising a battalion of 850 on Thursday.

Benin and Sierra Leone on Friday said they would contribute troops but did not say how many. Senegal said last week it would contribute troops if there were an intervention.

Most other countries in the 15-nation ECOWAS have so far either declined to comment or not yet taken a decision.

Russia's foreign ministry said it supported ECOWAS efforts to mediate but warned against any military intervention in Niger, saying it could destabilise the country and region.

France said it fully backed conclusions of the ECOWAS summit but did not outline any concrete support it would give to a potential intervention.

Niger's junta has yet to react to the prospect of a forceful intervention by ECOWAS. But it has rebuffed repeated calls for dialogue from the international community and named a new government hours before the summit.

Military governments in neighbouring Mali and Burkina Faso, have said they will defend the junta in Niger.

The African Union, the European Union, the US and the United Nations all said they were increasingly worried about Bazoum's detention conditions.

The UN Commissioner for Human Rights Volker Turk on Friday said the conditions were "rapidly deteriorating" and could amount to a violation of international human rights law.