Military chiefs from the West African bloc Ecowas will meet in Ghana on Thursday and Friday to discuss possible military intervention in Niger, sources said on Tuesday.
The meeting, originally scheduled for Saturday but then postponed, came after Ecowas leaders last week approved deployment of a "standby force to restore constitutional order" in Niger, whose elected president Mohamed Bazoum was toppled on July 26.
German Development Minister Svenja Schulze said on Tuesday during a visit to West Africa that the coup in Niger was "a setback that aggravates the complex development challenges in the country and in the Sahel".
"We call for the immediate release of president Mohamed Bazoum and for the full restoration of constitutional order in the Republic of Niger," Ms Schulze said in a statement on behalf of the Sahel Alliance.
Niger, an impoverished country of 25 million people, was seen as one of the last countries western nations could team up with in Africa's Sahel region to beat back an extremist insurgency linked to Al Qaeda and ISIS. Before last month's coup, Europe and the US had poured hundreds of millions of dollars into propping up Niger's military.
Mr Bazoum has been under house arrest with his wife and son in the presidential compound in the capital, Niamey, since he was ousted by the presidential guard.
The junta has faced international pressure to release and reinstate Mr Bazoum. Immediately after the coup, Ecowas gave the regime seven days to return him to power and threatened to use military force if that did not happen. The deadline came and went with no action from either side.
The junta appointed a new government last week and on Monday announced that Mr Bazoum would face charges of treason, which could lead to a death sentence under Niger's laws.
People close to the president and in his political party last week reported his family’s electricity and water supplies had been cut off and they were running out of food. The junta dismissed the reports and on Sunday accused West African politicians and international organisations of waging a disinformation campaign to discredit them.
Rights groups worry Mr Bazoum will not receive a fair trial because the junta's newly appointed justice minister is the former president of the country's military tribunal.
“We don’t trust him. He can’t embody ideal independence and free justice,” said Ali Idrissa, executive secretary of a local human rights group, the Network of Organisations for Transparency and Analysis of Budgets.
The 21-member cabinet appointed last week includes civilians and military officers, but the mixed messages from those claiming to run Niger continue.
Before the military accused Mr Bazoum of treason, a member of the junta’s communication team told journalists the regime had approved talks with Ecowas that would take place in the coming days.
A mediation team of Islamic scholars from neighbouring Nigeria that met the junta at the weekend also said it was open to dialogue with Ecowas.