An Egyptian opposition figure has said protests in Cairo's Tahrir Square will continue until President Mohamed Morsi reverses a decree granting himself extra powers.
Left-wing Hamdeen Sabahy, a former presidential candidate, has launched a movement called the Popular Current and joined several other opposition leaders to denounce the decree.
He told a news conference broadcast on television: "Our decision is to continue in the square, we will not leave before this declaration is brought down," he said.
He added that that Tahrir Square would be a model of an "Egypt that will not accept a new dictator because it brought down the old one".
It comes amid widespread anger in Egypt over Mr Morsi's decision.
Mr Morsi had sought to calm the anger over the decree, which effectively protects the president's decisions from any legal challenge.
A statement from his office said: "The presidency reiterates the temporary nature of the said measures, which are not meant to concentrate power, but ... to devolve it to a democratically elected parliament ... as well as preserving the impartiality of the judiciary and to avoid politicising it."
The statement also reaffirmed that the new powers - which Mr Morsi says were taken to protect Egypt's revolution from followers of former president Hosni Mubarak - would only apply until a new constitution is adopted.
The president met senior members of the judiciary, which has changed little since the Mubarak era, after they called the move an "unprecedented attack" on their authority.
Angry protesters clashed with police for a fourth consecutive day in central Cairo, as Egypt's stock market reacted with a nearly 10% fall.
Violence also flared at the Freedom and Justice Party headquarters in the Nile Delta town of Damanhour, south of Alexandria, with one person reportedly killed and dozens injured.
More than 500 people are believed to have been injured in violent protests since the decree was announced on Thursday.
Activists have staged a sit-in at Cairo's Tahrir Square - the symbolic hub of the popular uprising that forced Mubarak from power - and a mass protest has been called for Tuesday.
The Muslim Brotherhood cancelled its planned counter demonstration to "lessen congestion" and avoid "public tension".