Sunday marks the first anniversary of President's Mohammed Morsi's assumption of power as Egypt's first freely elected leader.
Thousands of Morsi's supporters have staged a sit-in since Friday in an eastern Cairo district not far from the presidential palace, the focus of protests later on Sunday to demand his ouster.
The youth group leading the campaign to force Morsi out said it had collected more than 22 million signatures from Egyptians who want the president to go. It was not possible to verify the claim.
Morsi's supporters have questioned the authenticity and validity of the signatures.
