The ECOWAS bloc ordered the activation of a stand-by force on Thursday, two weeks after generals ousted Bazoum in the seventh coup in West and Central Africa in three years.
The chiefs of staff meeting indicates West African nations are stepping up preparations to commit troops for a possible action to reverse the coup.
"One (meeting) is being planned for next week," the ECOWAS spokesperson said.
A Nigerian official and an Ivory Coast army source said the meeting would be held on Saturday in Ghana.
It was not yet clear how big the force will be, how long it will take to assemble, and if it will actually invade.
But the proposed mission has raised the spectre of deepening conflict in a strategically important region where Western powers have lost sway during the spate of coups and where Russian influence appears on the rise.
ECOWAS - the Economic Community of West African States - said all options were on the table and it still hoped for a peaceful resolution to the Niger crisis.
Security analysts said an ECOWAS force could take weeks or longer to assemble, potentially leaving room for negotiations.
Ivory Coast is the only country so far to specify how many troops it would send.
President Alassane Ouattara on Thursday promised a battalion of 850 troops.
Benin's army spokesman said on Friday it would contribute troops but did not say how many.
Senegal said last week it would contribute troops if there were an intervention.
Most other ECOWAS countries - including regional heavyweight Nigeria, which holds its rotating presidency - have so far declined to comment.
Gambia's defence minister Sering Modou Njie and Liberia's minister of information Ledgerhood Rennie told Reuters on Friday they had not yet taken a decision to send troops.
Military governments in neighbouring Mali and Burkina Faso, both ECOWAS members, have said they will defend the junta in Niger.
The junta has yet to react to ECOWAS' decision although it has given no indication that it might relinquish power.
The African Union, the European Union and the United States all said they were increasingly worried about Bazoum's detention conditions.
The African Union called on the international community to rally to "save the moral and physical integrity of" Bazoum and end what it called the "worryingly poor conditions" of his detention.
Human Rights Watch said it had spoken to Bazoum this week and he had told them his family's treatment in custody was "inhuman and cruel".
"My son is sick, has a serious heart condition, and needs to see a doctor," HRW quoted Bazoum as telling them.
Bazoum's daughter Zazia Bazoum, who is in France, told Britain's Guardian newspaper the junta was keeping him in deplorable conditions to try to pressure him to sign a resignation letter.
Reuters could not independently confirm the conditions of his detention.
The coup in uranium-rich Niger, one of the world's poorest countries but a key ally for the West in the fight against Islamist militants in the Sahel region, was triggered by internal politics but has repercussions far beyond its borders.
US, French, German and Italian troops are stationed in Niger as part of the fight against local affiliates of al Qaeda and Islamic State.
The capital Niamey was calm on Friday morning, but residents were angered by the threat of military intervention.
"Deep down inside, I'm not afraid, I'm going about my business," Balla Souleymane said of ECOWAS' decisions.
"I think this is just blackmail."
Since the coup, many Nigeriens have turned up at junta-organised rallies to show support for the generals, criticising Western powers and lauding Russia, mirroring reactions following recent coups in Mali and Burkina Faso, whose military juntas kicked out French forces after taking power.
The embassy of former colonial power France has been the target of protests in Niamey.
France said it fully backed all the conclusions of the ECOWAS emergency summit held on Thursday.
But it stayed clear of outlining any concrete support it could give to any potential intervention.
