What is clear, and what I indicated tonight to President Mubarak is my belief that an orderly transition must be meaningful, it must be peaceful and it must begin now 

U.S. President Barack Obama

The U.S. president spoke after prodding Mubarak into publicly admitting that his relentless era in charge of Egypt was coming to an end, in a message delivered privately in Cairo by veteran U.S. diplomat Frank Wisner.

"What is clear, and what I indicated tonight to President Mubarak is my belief that an orderly transition must be meaningful, it must be peaceful and it must begin now," Obama said, minutes after calling the Egyptian leader.

"He recognizes that the status quo is not sustainable and that a change must take place," Obama continued, in remarks directed at multiple audiences, including Mubarak, protesters, the Egyptian army and the American public.

His comments came on another dizzying day of emergency diplomacy in Washington and unprecedented scenes of protest in Egypt, as a million people took to the streets demanding Mubarak leave power by Friday.

A senior administration official said Obama's conversation with Mubarak was frank and direct. "He said it was clear how much he loves his country, and how difficult this is for him. President Obama explained to him that an orderly transition can't be prolonged, it must begin now," the official said.

Obama's intervention, in a live televised address from the White House, will likely be seen by some analysts as an attempt to convince Mubarak to leave sooner than he has planned so far.

 I want to commend the Egyptian military for the professionalism that it has shown while protecting the Egyptian people. We've seen tanks covered with banners and soldiers and protesters embracing in the streets. And going forward, I urge the military to continue its efforts to help ensure that this time of change is peaceful 

Obama

A U.S. official said on condition of anonymity that Obama had a "direct and frank" 30-minute telephone call with Mubarak, after the Egyptian leader made his concession in a speech protesters immediately branded as insufficient.

Obama "said it was clear how much (Mubarak) loves his country, and how difficult this is for him. President Obama also explained to him that an orderly transition can't be prolonged -- it must begin now," the official said.

That approach seemed to indicate that Washington may not be satisfied with a transition of power consummated only after elections due in seven months.

Another official added: "the question is (not) whether he leaves now or leaves later, but our message simply was that you've got to recognize what your people are telling you."

Obama commended the Egyptian military for allowing hundreds of thousands of people to protest peacefully against Mubarak's regime.

"I want to commend the Egyptian military for the professionalism that it has shown while protecting the Egyptian people," Obama said.

"We've seen tanks covered with banners and soldiers and protesters embracing in the streets. And going forward, I urge the military to continue its efforts to help ensure that this time of change is peaceful."

Obama has been walking a fine line for days, torn between demands for democracy that resonate with America's own political DNA, and a leader who has ruled with an authoritarian hand yet been a crucial U.S. ally for 30 years.

The president also appeared keen to guard against a descent into chaos in Egypt that could be sparked by a sudden revolution, amid fears here of a government hostile to U.S. goals likely to spawn wider regional instability.

 To the people of Egypt, particularly the young people of Egypt, I want to be clear, we hear your voices. I have an unyielding belief that you will determine your own destiny 

Obama

Pointedly, Obama, who made a soaring call for universal rights to be respected in his historic 2009 speech to Muslims in Cairo, also leaned closer than ever before to anti-Mubarak protesters.

"To the people of Egypt, particularly the young people of Egypt, I want to be clear, we hear your voices. I have an unyielding belief that you will determine your own destiny," Obama said.

The U.S. leader also spoke directly to Egypt's all-powerful military, a key center of power which may be pivotal in ushering Mubarak into history.

"I want to commend the Egyptian military for the professionalism that it has shown while protecting the Egyptian people," Obama said.

"We've seen tanks covered with banners and soldiers and protesters embracing in the streets; and going forward, I urge the military to continue its efforts to help ensure that this time of change is peaceful."

Wisner, sent on a mission to Egypt by the State Department, earlier told the Egyptian leader it would be best if he did not seek a new term in the upcoming elections.

"What's clear is that this is a movement that is gaining momentum, it's not going to go away. And it's not likely to be enough," a U.S. official said.

"The message was that his time in office was coming to an end."

"What's happened today shows that there's some recognition but the real question is will they (protesters) demand more, and it's entirely possible they will," the official added.

Critics have accused the U.S. administration of being slow to grasp the scale of upheaval in Egypt after similar protests toppled nearby Tunisia's longtime president on Jan. 14.

The Obama administration reached out on Tuesday, not only to Mubarak, but to other key players on both sides of the crisis. The U.S. ambassador to Egypt, Margaret Scobey, spoke to Nobel Peace laureate Mohamed ElBaradei, an opposition figure who has seen rising support from a broad swath of Egyptian groups.

U.S. Defense Secretary Robert Gates spoke with Mohammed Hussein Tantawi, Egypt's defense minister. The Pentagon declined to give details about the call.

A U.S. official said Scobey delivered a message to ElBaradei echoing that made by the Obama administration in public: Washington wants a political transition but will not seek to dictate Egypt's political future.

ElBaradei, the former head of the U.N. nuclear watchdog, returned to Egypt last week and has since seen growing support from opposition groups, including the banned Islamist group the Muslim Brotherhood, Christians, intellectuals and others.

Washington meanwhile ordered the departure of all non-emergency U.S. government staff from Egypt amid days of protests against Mubarak.

"The Department of State will continue to facilitate the evacuation of U.S. citizens who require assistance," State Department spokesman Philip Crowley said in announcing the move.

He said the departure was ordered "in light of recent events."