Egyptian President Mohammad Mursi has surprised the Egyptian political establishment by both dismissing the minister of defence a few days after appointing him to his first cabinet, and also cancelling the orders of the Supreme Council of the Armed Forces (SCAF) that curbed presidential powers. Field Marshal Mohammad Tantawi was minister of defence under former president Hosni Mubarak and had been the most prominent survivor of the old regime in the new Egypt. His continuation in the cabinet seemed to show how Mursi was prepared to get along with the military in order to build consensus, but this week’s powerful demonstration of presidential authority followed a few days after a major security fiasco in the Sinai when a police station was attacked and 16 policemen were killed by militants.

Mursi’s move is part of the inevitable struggle between the Muslim Brotherhood, which won both the general and presidential elections, and the military which controlled the interim government and want to protect the military’s privileged position in the Egyptian structure.

While there is no doubt that Mursi’s dismissal of Tantawi is firmly in his area of authority, the president can expect a challenge to his cancellation of SCAF’s constitutional declaration in June, which curbed presidential power and kept much of it in the hands of the military council. The Supreme Constitutional Court is likely to overturn this cancellation of SCAF’s supplemental constitutional declaration, and it may be that Mursi will have to accept such a ruling. Many in Egypt may feel that these moves may have been orchestrated in advance as the military knew that the incoming president would have to establish his authority at some stage.

But the move will reinforce Mursi’s standing with the revolutionaries who participated in the ousting of Mubarak and have been strongly critical of Mursi’s willingness to work with the military and retain them in power.

The dismissal of both the minister and the SCAF decree absolves Mursi of the charge that he was becoming an establishment figure.