Egypt president
Egypt's Islamist President-elect Mursi delivers a speech in Cairo's Tahrir Square Reuters

On the eve of his swearing-in ceremony, Egyptian president-elect Mohammed Mursi of the Muslim Brotherhood indirectly took on the ruling military council.

A day before the official ceremony on Saturday, Mursi addressed tens of thousands of Brotherhood supporters in the historic Tahrir Square in the capital Cairo.

Mursi took an informal oath to the president's office in front of his supporters saying: "I swear by God that I will sincerely protect the republican system and that I respect the constitution and the rule of law. I will look after the interests of the people and protect the independence of the nation and the safety of its territory."

Mursi, in an indirect snub to the ruling Supreme Council of Armed Forces (SCAF), said there was no power above people power. Since the people are the sources of power, only they can decide who can rule them, he asserted.

Field Marshal Mohammed Hussein Tantawi, the head of the army council, is expected to hand over power on Saturday which will be a televised ceremony. Tantawi, who was the defence minister in the Mubarak era, is likely to continue in the same post under Mursi.

Mursi will be sworn in by the Supreme Constitutional Court rather than by parliament since it has already been dissolved by a court a few days before the elections. Reports suggest Mursi may even take oath before the dissolved parliament.

The military council has been ruling Egypt since January 2011 uprising which ousted former dictator Hosni Mubarak.

The Islamist kept mum on establishing an Islamic order in the country while addressing the supporters as "Muslims and Christians of Egypt."

He insisted that he would be a president for all Egyptians and keep both his supporters and opponents at equal distance.

Mursi also vowed to keep relations with other countries as smooth as possible and avoid animosities.

The real test will begin once Mursi takes over office and how he deals with the military council.

The council declared sweeping powers for itself hours after the presidential voting and this has angered the Brotherhood.

The issue is bound to rise which will once again increase the friction between the ruling Brotherhood and the army.