A Protester runs to throw a tear gas canister away during clashes with the Egyptian riot police near Tahrir square in Cairo, Nov. 22, 2011. (AP)
Cairo (CNN) -- Egypt's interim military rulers plan to announce a 100-person assembly Friday to write a new constitution, a day after a top court declared parliament invalid and triggered renewed chaos over the country's leadership.
The streets of Cairo, packed more than a year ago with throngs demanding the ouster of Hosni Mubarak, remained relatively quiet Friday morning as Egyptians tried to figure out what the ruling meant for the presidential election.
Activists called for protests later Friday, accusing military rulers of plotting to retain a grip on power.
The court's ruling comes days before Egyptians decide the country's new president in a runoff election between the Muslim Brotherhood's Mohamed Morsi and Ahmed Shafik, the last prime minister to serve under Mubarak.
The Supreme Constitutional Court dissolved parliament after it had been in session for a little more that four months, after ruling Thursday that the constitutional articles that regulated parliamentary elections were invalid.
The Supreme Council of the Armed Forces -- the military rulers in control of the country since Mubarak's ouster -- claims full legislative power. It is widely expected to issue its own interim constitutional charter while it awaits the assembly to draft a new one.
While the military council did not issue a statement on the court's ruling, state media reported that military leaders have said the presidential runoff would still take place over the weekend.
In the same ruling that dissolved parliament, Egypt's high court cleared the way for Shafik to run after rejecting a new law that barred members of Mubarak's regime from running.
The election of a president without a parliament means that whoever wins the runoff will be in a powerful position and deal directly with the military rulers while a new constitution is written and new parliamentary elections are held.
Some called the move political as the parliament was dominated by Islamists, a group long viewed with suspicion by the military.
The court ruling was "a complete coup d'etat through which the military council is writing off the most noble stage in the nation's history," said Mohamed el-Beltagy, a senior member of the Muslim Brotherhood's Freedom and Justice Party.
Mohamed El Baradei, a 2005 Nobel Peace Prize winner who waged a failed presidential bid, called for the country's military rulers to postpone the runoff election.
"Electing president in the absence of constitution and parliament is electing an 'emperor' with more powers than deposed dictator. A travesty," he tweeted Friday.
Meanwhile, activists called for Friday protests.
A youth group, calling itself the April 6 Movement, took to Facebook to call for early evening demonstrations to protest what it described as a "soft coup" by the military rulers.
The group accused the military council of "trying to stay its best in power as long as they can in order to safeguard their interests, and we will not accept that at all," according to a Facebook posting.
Meanwhile, Amre Moussa -- a former foreign minister under Mubarak, Arab League chief and most recently presidential candidate -- offered an opposite view.
"It is not a political move," he said. "It is a legal matter that has been referred to a tribune by individuals."
Moussa said the previously instituted constitutional panel was "unsatisfactory for many parties" because of the influence in it held by the Muslim Brotherhood.