Suspension is the African Union's (AU) usual response to any interruption of constitutional rule by a member state.
"As mandated by the relevant AU instruments, the African Union Peace and Security Council decides to suspend the participation of Egypt in AU activities until the restoration of constitutional order," Admore Kambudzi, secretary of the Peace and Security Council, said after a meeting on Friday.
Meanwhile, Egypt's army announced a state of emergency in the provinces of South Sinai and Suez on Friday after Islamist gunmen attacked an airport in the Sinai town of El Arish, state newspaper Al-Ahram reported.
The report quoted the commander of the Third Field Army Osama Asakar as saying that the "state of readiness" had been raised to its highest level in the two provinces due to the attack.
The attack, the latest of a string of security incidents in the lawless region, came two days after the overthrow of former president Mohamed Morsi. It was not clear if the attacks were coordinated and in reaction to his removal.
Soldier killed
An Egyptian soldier was killed early on Friday in coordinated rocket and machinegun attacks by Islamist militants on army checkpoints and a police base in the restive Sinai, medics said.
Two other soldiers were wounded when Islamist militants fired on an army checkpoint near the north Sinai village of al-Gura. Elsewhere, militants attacked a police base with rockets, security sources said.
Hardcore Islamist militants have used the sparsely populated north of the peninsula as a launching pad for attacks on security forces and neighbouring Israel.
Following Morsi's ouster by the military on Thursday, several militants have publicly threatened violence in retaliation.
Morsi, elected in June 2012 and deposed on Wednesday after mass protests, had himself ordered a crackdown on Sinai militants after an August 2012 attack killed 16 soldiers. – Reuters; AFP