Ayman Nour is no longer party leader but still attracts great interest
A day after being freed from jail, Egypt's best-known opposition politician has said he will not resume the leadership of the party he founded.
"There is another chief of Ghad right now... I will work in the background to rebuild the party," Ayman Nour said.
Mr Nour served three years of a five-year jail term on forgery charges he said were politically motivated.
He was the main challenger to President Hosni Mubarak in Egypt's first multi-party presidential election in 2005.
Analysts say Mr Mubarak called the poll under pressure from the United States - a close ally and major aid donor - to introduce democratic reforms.
Amid chaotic scenes at the Ghad party headquarters, Mr Nour made a triumphant entrance.
The BBC's Christian Fraser, in Cairo, says it took 20 minutes before the chanting and ululating of his supporters finally subsided enough to allow Mr Nour to speak.
The press conference was held in a room gutted by fire late last year when rival factions within his party fought bitterly over the vacant leadership.
"I have not come out for revenge," said Mr Nour, "I have come out to do what they jailed me for. I am going to practise my role as a politician through the Ghad party."
Message for Obama
The leading opposition figure also recounted the conditions of his period in jail.
He said he was denied the food given to other prisoners, prevented from praying, and as a diabetic and sufferer of high blood pressure, denied proper medical care.
Throughout the press conference Mr Nour was very careful how he answered reporters, skirting around the question about whether he would run again, and notably there was no direct criticism of Mr Mubarak.
But if his release has been interpreted as a concession aimed at improving ties with the new White House administration then he says it is not something that pleases him.
"My message for President Obama," he said, " is we need to act in the interest of our people, not in the interest of the head of state."
Mr Nour is prohibited from seeking public office unless he receives a presidential pardon.