Police have fired tear gas to disperse supporters of Egypt's ousted Islamist president Mohammed Morsi from Tahrir Square in the capital, Cairo.
The clashes came as a panel amending the constitution adopted during his time in office agreed on text changes.
The revised charter preserves the military's wide-ranging powers - including the ability to try civilians in certain cases.
It will be put to a referendum which is expected to be held in January.
The 50-member panel completed a final draft after two days spent revising the charter adopted under former President Morsi.
Significantly, the timeline for elections has been changed so that it no longer specifies whether parliamentary or presidential elections should be held first.
The 247-article draft calls for the first election to take place within 90 days of the draft constitution being adopted by referendum. The other election should be held up to six months later, it says.
The chairman of the panel said the draft would be handed to interim President Adly Mansour on Tuesday.
The text also says women and Christians should have "suitable representation'' but says a future law must decide the details.
The proposed new constitution would require presidents to declare their financial assets, and allow lawmakers to vote out an elected president and call for early elections if they had a two-thirds majority.
Tahrir Square was the birthplace of the revolt that toppled long-time President Hosni Mubarak almost three years ago.