Egyptian President Mohammed Morsi retired the country's two top defense officials, just one week after militants attacked a police station in the Sinai peninsula, killing 16.

According to an announcement by Morsi's spokesman, Morsi deposed both chief of staff Sami Enan and Defense Minister Gen. Hussein Tantawi, naming both as his new advisers.

The statement added that the new head of the military would be General Abdellatif Sisi and Sidki Sobhi as the new chief of staff.

Morsi also cancelled a constitutional declaration aiming to limit presidential powers which the ruling army council issued in June as the election that brought him to power drew to a close.

The removal of Tantawi, who served under Hosni Mubarak, is the latest phase in the power struggle between the Egyptian military and the Muslim Brotherhood.

Last month, Tantawi raised the stakes in the military's political standoff with the Muslim Brotherhood, saying the armed forces will not allow a "certain group" to dominate the country.

Tantawi's comments came only hours after he met with U.S. Secretary of State Hillary Rodham Clinton, who urged him to work with Morsi on a full transition to civilian rule.

The military, which ruled after the fall last year of Hosni Mubarak, and the Brotherhood, the country's strongest political force, are in a competition over power that has intensified with Morsi's winning of the presidency last month.

Days before Morsi was sworn in on June 30, the Brotherhood-led parliament was dissolved and the generals gave themselves legislative and budgetary authority and control over the process of drafting a new constitution, put severe limits on the president's authority.

In his comments at the time, Tantawi did not specify the Brotherhood, but his reference that the military would not allow the group to hold sway was clear.

"Egypt will never fall. It belongs to all Egyptians and not to a certain group … the armed forces will not allow it," Tantawi told reporters after a handover ceremony for the transfer of command of the armed forces' 2nd Army in the Suez Canal city of Ismailia.

"The armed forces will not allow anyone, especially those pushed from outside, to distract it from its role as the protector of Egypt," he said. "The army will never commit treason and will continue to perform its duties until Egypt reaches the shores of safety."

Last week, armed attackers from the Sinai breached Israel's border in an armored personnel carrier stolen in a raid on an Egyptian police station that killed 16 Egyptian policemen.

The Fahd APC was hit in an Israeli air strike, preventing what military officials said could have been a deadly large-scale terror attack. A second personnel carrier exploded at the Kerem Shalom border terminal, which connects Israel, Gaza and Egypt, before the vehicle could enter Israeli territory.