Residents in Niger are being urged to help prepare for a possible invasion by its regional neighbours after a military junta overthrew the country's democratically elected president.
Nigeriens in Niamey, Niger's capital, are calling for a large-scale recruitment drive of volunteers to, among other functions, fight and provide medical care and engineering logistics to the junta.
The development comes after the West African regional bloc, ECOWAS, activated a "standby force" to restore order in Niger.
ECOWAS, whose members include Senegal, Nigeria and Ghana, said it will intervene militarily if the junta does not release and return Niger President Mohamed Bazoum to power.
In response, tens of thousands of Nigeriens are being encouraged to register with the Volunteers for the Defence of Niger group.
Amsarou Bako, one of its founders, said: "It's an eventuality. We need to be ready whenever it happens."
From Saturday, recruitment drives will be launched in Niamey and cities where invasion forces might enter, such as those bordering Nigeria and Benin - both countries have said they would participate in an intervention.
Anyone over 18 years old can register and the list will be given to the junta to call upon people if needed.
Mr Bako added the junta is aware of the initiative, but not directly involved.
President Bazoum was overthrown in July after junta leaders said he had failed to secure Niger against growing jihadi violence.
He has since been charged with "high treason" and is believed to be under house arrest.
In the weeks since President Bazoum was overthrown, tensions have grown between ECOWAS and the junta, although both sides have indicated a willingness to resolve the crisis peacefully.
ECOWAS defence chiefs are expected to meet this week for the first time since the bloc announced the deployment of its standby force.
The group has not indicated if or when its force would invade, although military analysts expect any invasion would include several thousand troops and have devastating consequences.
"A military intervention with no end in sight risks triggering a regional war, with catastrophic consequences for the vast Sahel that is already plagued by insecurity, displacement and poverty," said Mucahid Durmaz, senior analyst at Verisk Maplecroft, a global risk intelligence company.
Niger was seen as one of the last democratic countries in the Sahel region, south of the Sahara Desert, and a partner for western nations in the effort to beat back growing jihadi violence linked to al-Qaida and the Islamic State (IS) group.
France, the former colonial ruler of Niger, and the United States have approximately 2,500 military personnel in the region, which train Niger's military and, in the case of France, conduct joint operations.
However, since the coup, France and the US have suspended military activities and jihadi attacks are increasing.
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