Mena state news agency says ElBaradei met interim President Adly Mahmud Mansour, three days after the army removed Islamist leader Mohammed Morsi amid growing nationwide unrest.
The move has in turn triggered mass unrest by supporters of Morsi.
71-year-old ElBaradei is a former head of the United Nations nuclear watchdog.
He and other party leaders attended a meeting called by Mansour on Saturday.
ElBaradei leads an alliance of liberal and left-wing parties, the National Salvation Front.
A spokesman for the front told AP news agency that Mansour would swear him in as prime minister on Saturday evening, the BBC reported.
In an interview on Thursday, ElBaradei defended the army's intervention, saying: "We were between a rock and a hard place."
"It is a painful measure, nobody wanted that," he said. "But Mr Morsi unfortunately undermined his own legitimacy by declaring himself a few months ago as a pharaoh and then we got into a fist fight, and not a democratic process."
More than 30 people died and hundreds were wounded in Friday's protests by Islamist supporters of the deposed president.
Huge crowds have demonstrated again in Cairo on Saturday to demand his reinstatement.
Meanwhile opponents of Morsi have called for demonstrations against the Muslim Brotherhood, to which he belongs, on Sunday.
Morsi is in detention, along with some senior Brotherhood figures.
Image: Mohd Abd El Ghany/Reuters
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