Tamarod co-founder Hassan Shahin has announced he will go "on strike" until protesters arrested outside the Shura Council on Tuesday are freed.
"Down with Sisi," Shahin said in response to the police dispersal of a protest against military trials for civilians on Tuesday. Twenty-four activists are being detained by authorities.
The Tamarod spokesperson called on people to descend on Talaat Harb Square on Wednesday to stop the "police state" from returning in Egypt.
Tamarod led a popular uprising that prompted the Egyptian army to oust Islamist President Mohamed Morsy in July.
However on Tuesday state-run newspaper Al-Ahram reported that Mahmoud Badr, Mohamed Abdel Aziz, May Wahba and Shahin no longer represented Tamarod, according to other members of the group.
A campaign demanding the revocation of the protest law called for a press conference at 4 pm outside Qasr El-Nil police station.
On Facebook, the campaign said the conference will announce the first permission for protesting since the law was enacted days ago.
Presidential adviser Mostafa Hegazy meanwhile said the Interior Ministry had approved a protest by the campaign, as the activists notified Qasr El-Nil police station, for the first day of December.
Hegazy said in a talk show aired on the privately-owned TV Channel MBC Masr on Tuesday: “As far as I know, the ministry approved a request submitted to stage a protest against the law.:
