The African Union has suspended Niger following the takeover of the West African country by a military junta on July 26.

In a much-anticipated statement, the African Union (AU) -- a union of 55 member states -- announced its decision to "immediately suspend the participation of the Republic of Niger from all activities of the AU and its Organs and institutions until the effective restoration of constitutional order in the country."

The suspension was decided at a meeting on August 14 held by the AU's Peace and Security Council regarding the military coup in Niger.

The AU called on both its members and the international community to "reject this unconstitutional change of government and to refrain from any action likely to grant legitimacy to the illegal regime in Niger."

The AU Peace and Security Council also ordered an assessment of the decision by West African bloc, the Economic Community of West African States (ECOWAS) to prepare a standby force for potential deployment to Niger.

The council will review an assessment of the "economic, social and security implications of deploying a Standby Force in Niger," it said.

ECOWAS chiefs had initially given the junta a seven-day ultimatum to restore power or face consequences, including military action.

That planned action did not happen as many attempts at dialogue and diplomacy have been made by ECOWAS and allies such as US and the European Union.

A top ECOWAS official said Friday that the bloc is ready to push ahead with military intervention in Niger and had chosen the "D-Day."

The bloc's Commissioner for Political Affairs, Peace & Security Abdel-Fatau Musah told a press conference in Ghana that ECOWAS is not prepared to "engage in endless dialogue" with the junta and military forces are "ready to go anytime the order is given" for military intervention.

The African Union affirmed its "solidarity" with ECOWAS's efforts to restore constitutional order in Niger "through diplomatic means," it said.

In the official statement, the African Union urged the military junta to prioritize "the supreme interests of Niger and its people above all else," and "to immediately and unconditionally return to the barracks, and submit to civilian authorities consistent with the Constitution of Niger."

The AU suspension comes days after the junta proposed a return to democracy within three years.

Niger's military ruler General Abdourahamane Tchiani, who ousted President Mohamed Bazoum and seized power in a coup, said during a televised address on Saturday evening that neither the junta "nor the people of Niger want war and remain open to dialogue."

He said the principles of the transition would be decided within the next 30 days as part of a national dialogue hosted by the junta and the transition itself "should last no longer than three years."