An Islamist backed by the Muslim Brotherhood declared victory as Egypt's first democratically elected president even as the country's military rulers issued a decree that stripped the position of much of its power.

The move by the Supreme Council of the Armed Forces -- who have run Egypt since the ouster in February 2011 of Hosni Mubarak -- came Sunday at the conclusion of a two-day presidential runoff.

Even with no constitution, no parliament and, possibly, little power, the Muslim Brotherhood's Mohamed Morsi declared victory late Sunday over Ahmed Shafik, who was Egypt's prime minister in the final days of the regime of Mubarak.

Unofficial results released Monday by the state-run Al-Ahram news website showed Morsi with 11.2 million votes, or 52.3%, compared with 10.3 million for Shafik.

Shafik did not concede, saying votes had not yet been tallied in his stronghold districts, including portions of Cairo.

Whoever emerges as the winner, his power will be limited.

Under an interim constitutional declaration released Monday by the military council, the military council retains the power to make laws and budget decisions for the country until a new constitution can be written and a new parliament elected.

The declaration says Supreme Council members "shall decide all matters related to military affairs, including the appointment of its leaders."

The president has the power to declare war, it says, but only "after the approval of the SCAF."

In the event of unrest in the country, like that which preceded Mubarak's ouster, the president can involve the armed forces to provide general security, but only "after receiving the approval of the SCAF," it says.

Under the military council's decree, Egypt's new constitution must be drawn up within three months.

The president will set the date for new parliamentary elections, and he will have the power to pardon. He also will have the ability to appoint government officials and ambassadors.

Last Thursday, the high court ruling that invalidated parliament and paved the way for the military council to dissolve the legislative body was derided by Morsi's spokesman as "a soft military coup." The spokesman, Jihad Hadad, said it was "full of legal loopholes."

In a victory speech on Monday, Morsi did not address the move by the military council.

Rather, he tried to allay fears that he would impose an Islamist state, promising "a civil, patriotic, democratic, constitutional and modern state."

"No one's rights will be left out of it, and no one will dominate over the other," he said in a speech at his campaign headquarters in Cairo. "The strong will not oppress the weak, and the weak's rights will not be forgotten because of irresponsibility."

In an interview on CNNI's "Amanpour," Morsi spokesman Jihad Haddad said all Egyptians will enjoy freedom "in every one of their choices, even religion" under Morsi.

"Everything that has been echoed about the Muslim Brotherhood is probably much more lies than truth," Haddad said. "In reality, we are much more liberal than everyone else thinks we are."

Haddad said he is unfazed by the military's assertion of power over the parliament and over the presidency. "Everything is running smoothly," he said, adding that parliament plans to meet this week as planned, potentially forcing a confrontation with military rulers and Egypt's high court.

As Morsi's supporters gathered in Cairo's Tahrir Square to celebrate, some questioned the impact of the decree.