Dr Abdullah Al-Ashaal, a law professor at the American University, said that Abdel Fattah Al-Sisi's call for Egyptians to demonstrate could lead Egypt into a cycle of violence and civil war.
Al-Ashaal stressed that Al-Sisi's call to his supporters to protest on Friday is a loose and dangerous invitation that threatens the unity of the Egyptian army itself.
Al-Ashaal said that the people in the squares do not grant authorisation to Al-Sisi and the use of force must be governed by the law, he pointed out that crowding in the squares puts the Egyptian army at risk.
He also stressed that Al-Sisi's invitation was "illegal", because the authorisation to use force cannot be obtained from the streets, but must come from elected representatives and it could lead to civil war.
Al-Ashaal called on the army to confront "the state security officers who are thugs and beat people in the squares and to secure the entrances and exits of cities, peaceful protests and prevention of any civilian carrying a weapon. Moreover, communication must be secured between provinces, as the army plays a role in restoring national unity."