Leaders of the country’s opposition movements are already warning of the risk of another military-backed president for life if the military elite currently negotiating a transition from Mr. Mubarak were to block broader change.
But several groups of prominent intellectuals and political analysts are pushing plans to endorse an initial transfer of power to Mr. Suleiman, who already appears to be governing in Mr. Mubarak’s place, they said.
“The reality on the ground is that the vice president is the one managing the situation and what we want to do is legalize it,” said Wahid Abdel Neguid, the deputy director of the Al Ahram Center for Political and Strategic Studies and one of the figures working on the plans. “Given the current situation, the president really can’t do anything, not here and not abroad, given the amount of pressure that is on him.”
The groups putting forward the proposal include Nabil Fahmy, former Egyptian ambassador to the United States; Naguib Sawiris, one of the most prominent businessmen in Egypt; Ahmed Kamal Aboul Magd, a lawyer and influential Islamic thinker; and Ahmed Zewail, a Nobel Prize-winning chemist. One group met Friday at the office of Amr Moussa, the head of the Arab League and perhaps the most popular political figure in Egypt.
Mr. Suleiman, a former military officer, appears to share power with two close allies, Field Marshal Mohamed Tantawi, the defense minister, and Ahmed Shafiq, the prime minister, a retired general who previously ran the country’s national airline, said Abdel Moneim Qattou, a retired Army general close to all three.
But the three find themselves squeezed between their loyalties to Mr. Mubarak on one side and the military on the other, Mr. Qattou said. They have been unwilling to push Mr. Mubarak out, he said. But they are also unwilling or unable to deploy the military against the protesters — a move that would cut deeply against its self-image and prestige.
“The three of them are military men,” Mr. Qattou said. “They know each other very well and they are together trying to find a way out of this crisis. They want to do this without spilling blood and without hurting the dignity of Egypt or Mubarak while fulfilling the demands of the masses.”
There appeared to be signs on Friday that the three men may be recalibrating their positions. Mr. Shafiq announced for the first time that the government would make no effort to clear Tahrir Square, allowing the protesters to remain indefinitely.
Field Marshal Tantawi, meanwhile, visited the square himself in the morning to inspect the troops stationed around the Egyptian Museum. It was the first appearance there by any of the country’s top officials, and protesters and military experts took it as a signal to Mr. Mubarak’s plainclothes supporters not to assault the square again.
A cheer rose from the protesters as soon as Field Marshal Tantawi appeared, and they clasped hands to form a barrier around the area where he was walking. Several said they wanted to ensure that no Mubarak-supporting provocateur tried to incite violence.
Mr. Obama repeated twice at his news conference that exactly how the transition would occur is “not a decision ultimately the United States makes or any country outside of Egypt makes.” But he laid out a series of principles that seemed designed to hem Mr. Mubarak in, and reduce his options.
“Going back to the old ways is not going to work,” he said. One official said that these messages were being reinforced in what he called an effort to “flood the zone” with calls to military leaders, members of the Egyptian elite, and legislators. Secretary of Defense Robert M. Gates made another call to his Egyptian counterpart on Friday, part of the effort to assure that the military kept enough peace on the streets for serious discussions with the opposition to begin.
Opposition leaders contend that the existing Constitution so favors the governing party that it should be thrown out immediately and that Parliament, which is dominated by Mr. Mubarak’s party, should be disbanded.
In the opening stages of what promises to be a protracted round of negotiations, the diplomat Mohamed ElBaradei said in a news conference at his home near Cairo that opposition lawyers were preparing an interim Constitution. He said the opposition was calling on Mr. Mubarak to turn over power to a council of two to five members who would run the country until elections within a year.
Only one member would come from the military, Mr. ElBaradei said, adding that the armed forces’ most important task now was to “protect Egypt’s transition period in a smooth manner.”
“We have no interest in retribution,” he said. “Mubarak must leave in dignity and save his country.”
Mohamed el-Beltagui, a leader of the Muslim Brotherhood, the outlawed Islamist group that had been the major opposition in Egypt until the secular youth revolt, said that the organization would not run a candidate in any election to succeed Mr. Mubarak as president.
David D. Kirkpatrick reported from Cairo, and David E. Sanger from Washington. Anthony Shadid, Kareem Fahim, Mona El-Naggar and Liam Stack contributed reporting from Cairo; and Alan Cowell from Paris.