Thousands of Egyptians urged the powerful army chief to run for president during a rally that also called for the third anniversary of the country's revolt to be used as an occasion to thank the military for overthrowing the former Islamist president.
The move on Tuesday angered pro-democracy advocates, already facing a campaign of intimidation and attacks by much of the Egyptian media.
The former security officers and army loyalists organising the campaign, called "complete your good deed", aim to boost support for Defence Minister General Abdel-Fattah el-Sisi, who removed president Mohammed Mursi in a July 3 coup.
The general has yet to announce his intentions. A referendum that last week approved a new constitution saw an unexpectedly modest turnout, denying him the robust popular mandate he allegedly sought as a rationale to make a run for office.
"At the top of our priorities is to choose a nationalist leader," former interior minister Ahmed Gamal Eddin told the crowd at Cairo Stadium, where banners read: "Egypt calls upon you."
Standing next to him, Coptic priest Bolous Awida described Sisi as "the soaring eagle" and led chants of "El-Sissi is my president". Former grand imam Ali Gomaa said: "The army, the police and Egypt order you to complete your good deed."
Parliamentary and presidential elections are the next step of the military-backed transition plan, introduced by interim authorities.
Some 98 per cent of voters endorsed the draft constitution, drawn up by a panel of mostly secular-minded politicians and experts after the military suspended the Mursi-era 2012 charter during the coup. But turnout was only 39 per cent.
The push for Sisi to run came as Mursi's group, the Muslim Brotherhood, called for mass protests to mark January 25, 2011, the first day of an 18-day uprising that forced autocrat Hosni Mubarak to step down.
Liberal and secular-minded activists have also made similar calls but said they will not join forces with rival Islamists in their rallies.
Demonstrators originally chose the January 25 date because it was a national holiday honouring the notorious security forces and they wanted to defy them on the same day. The day then became a national holiday to mark the rebellion against authorities.
On Tuesday, however, to the dismay of pro-democracy activists, Eddin called upon Sisi supporters at the rally to revert the holiday to its original meaning, celebrating the police.
In anticipation of unrest, the Interior Ministry has said it would deploy some 400,000 security forces to prevent any act of violence, and that police stations would be guarded with heavy weapons.
Hours earlier, a Cairo Appeals Court set February 16 as the start date for one of four trials of Mursi and top Muslim Brotherhood leaders. This one is on charges of conspiring with militant groups such as Palestinian Hamas and Lebanese Hezbollah, as well as with Iran, to destabilise Egypt.
His supporters have called the conspiracy accusations implausible. Mursi was most recently referred to court over insulting the judiciary. Charges in the other three trials, including inciting the killing of his opponents and organising jailbreaks, carry the death penalty.