Washington (CNN) -- As protesters on the streets of Cairo continued to demand that Egyptian President Hosni Mubarak step down, there were new glimpses into the sensitive diplomatic strategy the Obama administration is using to help bring about a transition in which Mubarak himself helps to dismantle his own power structure.
U.S. Secretary of State Hillary Clinton, speaking at the Munich Security Conference, urged support for the man Mubarak named to carry out that transition, Vice President Omar Suleiman.
"There are forces in at work in any society," Clinton said, "in particular in one that is facing these kinds of challenges, who will try to derail or overtake the process to pursue their own specific agenda, which is why I think it's important to support the transition process announced by the Egyptian government actually headed by now-Vice President Omar Suleiman."
Clinton said President Hosni Mubarak "has given a clear message to his government to lead and support this process of transition." Negotiations are beginning, she said, on constitutional reform and on setting up and legitimizing nonviolent political parties.
"That is what the government has said it is trying to do," Clinton added. "That is what we are supporting, and hope to see it move as orderly but as expeditiously as possible, under the circumstances."
But at that same forum, top diplomats from around the world heard a somewhat different message from a former ambassador whom U.S. President Barack Obama dispatched last week to negotiate directly with Mubarak.
Speaking in a videolink from New York, Frank Wisner said the Egyptian president should stay in office, at least for now, to help push through crucial political changes.
"We need to get a national consensus around the preconditions for the next step forward," Wisner said. "The president must stay in office in order to steer those changes through."
Without defining how long the Egyptian president should stay, Wisner said: "I therefore believe that President Mubarak's continued leadership is critical. It's his opportunity to write his own legacy." Wisner warned that protesters on the streets of Cairo might end up cheated of real political change without real reform leading to free and fair elections and an end to the repressive political structures Hosni Mubarak put in place.
U.S. officials at the conference stressed Wisner was speaking for himself as an expert and not for the Obama administration. State Department spokesman P.J. Crowley issued a statement saying "We have great respect for Frank Wisner and we were deeply appreciative of his willingness to travel to Egypt last week," but added that Wisner "has not continued in any official capacity following the trip. The views he expressed today are his own. He did not coordinate his comments with the U.S. government."
A senior administration official, speaking on background because of the diplomatic sensitivity of the issue, told CNN, "We agree with many things he said, but not all. His perspective is valuable."
Wisner's comments echoed those of senior U.S. officials who told CNN this week: "The U.S. recognizes that certain legitimate legislative hurdles need to be taken care of before Mubarak goes. While he should take care of them sooner rather than later, it is going to take some time."
From Washington, Vice President Joe Biden did some telephone diplomacy Saturday with Vice President Suleiman. Biden, the White House said, asked about progress in beginning "credible, inclusive negotiations for Egypt's transition to a democratic government to address the aspirations of the Egyptian people."
The White House said he stressed the need for a "concrete reform agenda, a clear timeline and immediate steps that demonstrate to the public and the opposition that the Egyptian government is committed to reform."
From the White House, Obama called several international leaders to discuss the ongoing situation in Egypt, including Crown Prince Mohammed bin Zayed of the United Arab Emirates, British Prime Ministers David Cameron and German Chancellor Angela Merkel. Sticking close to the comments since the crisis in Egypt began, Obama, his spokesman said, emphasized the importance of an "orderly, peaceful transition, beginning now."