Tens of thousands packed Tahrir Square on Tuesday to protest a power grab by Mohamed Morsi, piling pressure on Egypt's Islamist president as he faces his most divisive crisis since taking power in June.
The huge turnout in the iconic square in the heart of Cairo, expected to swell further at the end of the workday and with the arrival of several marches from across the capital, marked the largest mobilisation yet against the president.
Thousands of lawyers had earlier left their syndicate chanting, "The people want the downfall of the regime," -- the signature chant of the protests that toppled Hosni Mubarak last year-- as they made their way to the square.
In the Mediterranean city of Alexandria, thousands gathered in Qait Ibrahim square, with two large marches expected to join them later.
A few dozen members of the the Muslim Brotherhood, on whose ticket Morsi ran for office, tried to start their own demonstration nearby but were kicked out.
"Down with the rule of the Supreme Guide," the protesters chanted, in reference to the head of the powerful Islamist group, a chant echoed in the Red Sea resort of Sharm el-Sheikh, where hundreds took to the streets.
A rival rally in Cairo by the Muslim Brotherhood in support of the president was called off to "avoid potential unrest" but that has done little to abate the division among supporters and foes of Morsi.
"The Muslim Brotherhood stole the revolution" read one banner in Tahrir. Another said the president was "pushing the people to civil disobedience."
"The Muslim Brotherhood are liars," read another.
Sporadic clashes between police and protesting youths continued into the afternoon near Cairo's Tahrir Square.
"We will stay in Tahrir until Morsi cancels his declaration," protester Ahmed Fahmy, 34 told AFP.
The demonstrations come a day after Morsi met with the country's top judges in a bid to defuse the crisis over the decree, that has sparked deadly clashes and prompted judges and journalists to call for strike.
The protesters are angry at the decree that Morsi announced last Thursday allowing him to "issue any decision or law that is final and not subject to appeal", which effectively placed him beyond judicial oversight.
The decree put him on a collision course with the judiciary and consolidated the long-divided opposition which accuses him of taking on dictatorial powers and raise fears that the Islamists will be further ensconced in power.
After a meeting on Monday with top judges aimed at defusing the dispute, Morsi stuck by his controversial decree.
There is "no change to the constitutional declaration," presidential spokesman Yasser Ali told reporters at the end of the meeting.
But he added that Morsi sought to clarify that any irrevocable decisions apply only to issues related "to his sovereign powers" and stressed the temporary nature of the decree.
In a statement, the head of the Freedom and Justice Party (FJP) -- the political arm of the Muslim Brotherhood-- said the meeting between Morsi and the judges had been "fruitful."
But judges at the meeting said the crisis was not over.
"The meeting failed," Judge Abdel Rahman Bahlul, who attended the talks, told the independent daily Al-Masry Al-Youm.
"We cannot say this is the end of the crisis between the judiciary and the presidency," another judge who attended the talks, Judge Ahmed Abdel Rahman, told the paper.
A judicial source told AFP that even if immunity were limited to sovereign powers, "which appears to be a compromise, there are still concerns that the text itself remains unchanged."
Morsi's decree has led to charges that he is taking on dictatorial powers.
Some courts have suspended work in protest, and journalists have decided in principle to strike.
Angry demonstrators have also torched offices belonging to the Muslim Brotherhood's Freedom and Justice Party (FJP).