Supporters of Egypt's ousted Islamist President Mohamed Morsy called on Thursday for daily protests in the four days before his trial on 4 November, raising the danger of more violence in a crisis that has already cost hundreds of lives.
Morsy, who was ousted by the army on 3 July after mass demonstrations against his rule, is due to appear in court on Monday along with 14 other senior Muslim Brotherhood figures on charges of inciting violence.
The trial could further inflame tensions between the Brotherhood and the army-backed interim government as it struggles to restore stability in the most populous Arab state.
"The Alliance calls on all proud, free Egyptians to gather in the squares in protest against these trials... starting on Friday," the Brotherhood and its allies said in a statement.
It urged crowds to move on Monday to a police institute near Cairo's Tora prison, where the trial is expected to take place.
The charges relate to the deaths of about a dozen people in clashes outside the presidential palace in December after Morsy enraged his opponents with a decree expanding his powers.
Morsy has been held in a secret location in the four months since his overthrow. In that time Islamist militants have staged almost daily attacks in the Sinai Peninsula. Supporters and opponents of the Brotherhood have often clashed in the streets.
Backers of Morsy, Egypt's first freely elected president, say his removal was a coup, reversing the gains of the popular uprising which toppled autocrat Hosni Mubarak in 2011.
The army says it was responding to the will of the people.
Security officials accuse Brotherhood leaders of inciting violence and terrorism. Hundreds of the Brotherhood's members have been killed and many of its leaders have been jailed in one of the toughest security crackdowns in the movement's history.
A court order has banned the Brotherhood, Egypt's oldest and best organized Islamist movement, and seized its funds.
The Brotherhood denies any links with violent activity.