Over 50,000 protesters rallied in Cairo's Tahrir Square, in the biggest demonstration since January, when an 18-day uprising toppled President Hosni Mubarak.
The protesters, mostly bearded men and veiled women, sang religious and political chants, calling on the military government to transfer power to elected civilian rule. They have dubbed the protest "Friday of the One Demand" in reference to opposition to a draft constitution granting unrestricted power to the army.
"Earlier this month, Deputy Prime Minister for Political Affairs Ali El-Selmi proposed the principles, which, critics say, will grant the ruling Supreme Council of the Armed Forces (SCAF) supra-constitutional powers and put unfair conditions on the formation of a provisional assembly that will be mandated with drafting a new constitution," Egyptian daily Ahram explained.
The family of jailed activist and blogger Alaa Abd El Fattah have called for his supporters to flock to Tahrir Square to mark his birthday and call for an end to military trials.
Dozens of political parties and groups said in a joint statement they would rally "to protect democracy and the transfer of power" after negotiations broke down between Islamist groups and the cabinet.