US President Barack Obama led increasingly hoarse Western calls for "concrete" change in Egypt after President Hosni Mubarak wrong-footed the world by deciding to cling to power.
Obama issued a strongly-worded statement after a day of drama in Cairo in which hopes that Mubarak would step down were replaced by fury as he only went as far as ceding some authority to Vice President Omar Suleiman.
"The Egyptian people have been told that there was a transition of authority, but it is not yet clear that this transition is immediate, meaningful or sufficient," Obama said.
"Too many Egyptians remain unconvinced that the government is serious about a genuine transition to democracy, and it is the responsibility of the government to speak clearly to the Egyptian people and the world.
"The Egyptian government must put forward a credible, concrete and unequivocal path toward genuine democracy, and they have not yet seized that opportunity."
The European Union and Australia also pleaded for change and Germany said Mubarak had not allayed the fears of the world, but, above all, there was widespread shock that the 82-year-old Arab strongman had not resigned.
"Egypt will explode," leading Egyptian dissident Mohamed ElBaradei wrote on the Twitter website. "Army must save the country now."
Earlier, several hours before Mubarak addressed an expectant nation, CIA Director Leon Panetta had given credence to media reports that the veteran Egyptian leader was about to announce his immediate departure.
And when Obama followed up, perhaps unwisely, by telling Americans, "we are witnessing history unfold," most observers felt sure the US government expected Mubarak to go.
CNN quoted one unnamed US official after Mubarak's speech as saying it was, "not what we were told would happen, not what we wanted to happen."
Obama, whose administration has been criticized by some for a flat-footed response to the Egypt crisis, took several hours to issue a written response after holding an emergency meeting of his national security team.
When it eventually came, it was his strongest rebuke yet for the Egyptian government, but there was noticeably no mention of Mubarak by name and no threat to withhold the longtime US ally's crucial military aid.
Obama told Egypt to "move swiftly to explain the changes that have been made, and to spell out in clear and unambiguous language the step by step process that will lead to democracy and the representative government."
"Going forward, it will be essential that the universal rights of the Egyptian people be respected," he said.
"There must be restraint by all parties. Violence must be forsaken. It is imperative that the government not respond to the aspirations of their people with repression or brutality. The voices of the Egyptian people must be heard."
There were also strong calls for change from the EU's chief diplomat Catherine Ashton and from Australian Prime Minister Julia Gillard, among others.
"The time for change is now," Ashton said. "The demands and expectations of the Egyptian people must be met. It is for them to judge whether the steps announced by President Mubarak fullfil their expectations and aspirations."
Gillard said she was watching with concern after crowds in Cairo's Tahrir Square reacted angrily to Mubarak's televised speech.
"We do believe there has to be fundamental reform. We do believe that change has to come," Gillard said. "We do understand the status quo is not a tenable position. But we do want to see peace in the transition."
German Foreign Minister Guido Westerwelle expressed disappointment, saying Mubarak's speech was not the step forward that had been hoped for.
"The worries of the international community are rather bigger after this speech than before," he said from New York.
British Foreign Secretary William Hague called for for an "urgent but orderly transition" in Egypt but drew back from drawing firm conclusions.
"We're studying very closely what the president and the vice president of Egypt have said," Hague told the BBC.
Hague said it was not clear what powers Mubarak had transferred to his vice president, Omar Suleiman. Egypt's ambassador to the United States, however, insisted that Suleiman was now the de facto head of state.
"The president indicated very clearly he was transferring all his presidential authority to the vice president," ambassador Sameh Shoukry told CNN.
UN CALLS FOR PEACEFUL TRANSITION
UN Secretary-General Ban Ki-moon stressed that Egyptians must decide their own political future as he reiterated his call for a peaceful transition to free and fair elections.
A statement from his office said the United Nations stood "ready to assist in the process" and urged the Egyptian leadership to ensure protesters could voice their grievances without fear of violence.
UN Secretary-General Ban Ki-moon that Egyptians must decide their own political future as he reiterated his call for a peaceful transition to free and fair elections.
"The Secretary-General has been closely monitoring developments today in Egypt," his office said in a statement issued after President Hosni Mubarak disappointed angry crowds in Cairo by clinging to power.
In an eagerly anticipated announcement, Mubarak said he was handing over powers to Vice President Omar Suleiman but refused to tender his resignation and leave office as the protesters desire.
"The Secretary-General reiterates his call for a transparent, orderly and peaceful transition that meets the legitimate aspirations of the Egyptian people and includes free, fair and credible elections," Ban's statement said.
"He emphasizes that it is for the Egyptian people to determine their future. The Secretary-General calls again for any transition to fully respect human rights, and to ensure genuine and inclusive dialogue with all stakeholders."
Ban's statement said the United Nations stood "ready to assist in the process," and repeated a call on the Egyptian leadership to ensure protesters could voice their grievances without fear of violence.