File photo: The African Union headquarters in Addis Ababa. AFP
The Peace and Security Council "requests the AU Commission to undertake an assessment of the economic, social and security implications of deploying a standby force in Niger and report back to Council," the bloc said, following strong differences on the matter.
Army officers toppled President Mohamed Bazoum on July 26, prompting the West African regional bloc ECOWAS to threaten to use force to reinstate him.
ECOWAS -- the Economic Community of West African States -- agreed to activate a "standby force" as a last resort to restore democracy in Niger.
It has said it is ready to act, even as it continues to pursue hopes for a diplomatic solution.
The AU last week held a meeting on the crisis against a backdrop of divergent views within the bloc over any military intervention.
The coup has heightened international worries over the Sahel, which faces growing jihadist insurgencies linked to Al-Qaeda and the Islamic State group.
Niger is the fourth nation in West Africa since 2020 to suffer a coup, following Burkina Faso, Guinea and Mali.
The juntas in Burkina Faso and Mali have said that any military intervention in their neighbour would be considered a "declaration of war" against their countries.
The coup is the fifth in Niger's history since the impoverished landlocked state gained independence from France in 1960.
Bazoum's election in 2021 was a landmark, opening the way to the country's first peaceful transition of power.
He has been held with his family at the president's official residence since the coup, with growing international concern over his conditions in detention.
Short link: