West African regional bloc ECOWAS will hold a summit in Nigeria's capital Abuja on Thursday to discuss the coup in Niger, ECOWAS spokesperson Emos Lungu said on Monday.
This follows elapsing of the deadline from ECOWAS to Niger to reinstate president President Mohamed Bazoum.
The bloc had threatened to use force if the coup leaders fail to restore constitutional order by Sunday.
After the ultimatum passed, uncertainty continues over the situation with many experts warning on the potential impact of military intervention.
ECOWAS had sent two separate delegations last week to meet with the coup leaders and the deposed president in Niamey. But no progress had been made in those visits.
Mali and Burkina Faso have already sent a joint official delegation in a show of solidarity with Niger's junta. The two countries are also under military rule following coups.
"Burkina Faso and Mali are sending a delegation to Niamey," the Malian army said. "The aim: to demonstrate the solidarity of the two countries with the brotherly people of Niger."
Niger has closed its airspace due to the "threat of intervention" as the junta defied a deadline from the West African bloc ECOWAS to reinstate democratically elected President Mohamed Bazoum or face possible military action.
ECOWAS issued its ultimatum a week ago, demanding the generals relinquish power by midnight Sunday (2300 GMT).
Bazoum was overthrown on July 26 when members of his own guard detained him at the presidency.
