A new draft constitution for Egypt will be put to a referendum on 15 December.
President Mohammed Mursi made the announcement before the constituent assembly, which approved the draft document on Friday.
Both the draft constitution and a recent decree giving Mr Mursi sweeping new powers have prompted widespread protests by opponents of the president.
However, his supporters held their own demonstrations at the University of Cairo on Saturday.
After receiving a copy of the document, Mr Mursi called "all Egyptians to a referendum on the draft constitution on Saturday, 15 December".
In an address to the nation on Saturday, the president called for a comprehensive national dialogue.
"I renew my call for opening a serious national dialogue over the concerns of the nation, with all honesty and impartiality, to end the transitional period as soon as possible, in a way that guarantees the newly-born democracy," he said.
If approved, the new text will overwrite all constitutional declarations - including Mr Mursi's decree issued on 22 November - and a new parliament should be elected within 60 days.
The BBC reports the constituent assembly passed all 234 articles during a marathon session that began on Thursday and continued through the night.
Opponents walked out of the assembly saying the changes were being forced through.
"The struggle will continue," former IAEA head Mohamed ElBaradei tweeted on Saturday. He said the draft constitution undermines basic freedoms and violates universal values.