The 15-nation Economic Community of West African States (ECOWAS) demanded the "immediate release and reinstatement" of elected President Mohamed Bazoum, who has been held by the military since Wednesday.
"In the event the authorities' demands are not met within one week (ECOWAS will) take all measures necessary to restore constitutional order in the Republic of Niger. Such measures may include the use of force. For this effect, the chiefs of defence staff of ECOWAS are to meet immediately," the bloc said in a statement after its summit in Abuja, Nigeria, on Sunday.