US Middle East envoy William Burns will arrive in Cairo on Friday night, a senior Egyptian official said, as international efforts to resolve Egypt's political crisis ramp up.

"Burns is arriving tonight. He will meet with foreign minister Nabil Fahmy tomorrow," the source told AFP.

Burns, the under secretary of state for the Middle East, has already visited Egypt once since the July 3 ouster of president Mohamed Morsi.

His latest trip comes after EU foreign policy chief Catherine Ashton visited in a bid to mediate a peaceful solution to the stand-off between Morsi supporters and the army-installed interim government.

EU Middle East envoy Bernardino Leon and German Foreign Minister Guido Westerwelle have also held talks in Cairo this week to urge both sides to reach a compromise.

US Secretary of State John Kerry sparked an uproar among Morsi supporters on Thursday after saying the military was "restoring democracy" when it deposed the the Islamist president.