Mohamed ElBaradei will not run in Egypt's presidential election and will announce his withdrawal later on Saturday, a source on his campaign team told Reuters.
"ElBaradei will announce his withdrawal from the presidency bid," the source, speaking on condition of anonymity, said.
ElBaradei, a former head of the UN's nuclear watchdog body, had been seen as a frontrunner for the presidency, a post that has been empty since Hosni Mubarak was toppled from power by a mass uprising last February.
But his campaign has been weakened by divisions. In November, some of his campaigners quit, saying he had become cut off from his grassroots base.
ElBaradei has been criticised for being out of touch with ordinary Egyptians.
The military council which assumed Mubarak's powers says it will hand authority to an elected president by the end of June. It has yet to set a date for the presidential election.