World Leaders Say Mubarak Transition Must Start Now

World powers said Wednesday that the transition towards democracy in Egypt must begin immediately and called for calm amid clashes in Cairo after Hosni Mubarak vowed to cling to office until September.

U.N. Secretary General Ban Ki-Moon called attacks on peaceful protestors "unacceptable" as pro- and anti-Mubarak demonstrators fought each other in the city's central Tahrir Square, leaving at least 500 injured.

The 82-year-old, president of Egypt for the last 29 years, had hoped that his promise in a televised address on Tuesday night would buy him some breathing space, both from protestors and on the international front.

But it soon became clear that his attempt to shut down the argument had failed, with U.S. President Barack Obama among those indicating that his pledge to leave power after September elections did not go far enough while Turkey's prime minister said Mubarak should stand down now.

"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 after a phone call with the long-time U.S. ally.

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

The European Union's foreign affairs chief Catherine Ashton insisted that Mubarak address the transition "as quickly as possible" while the leaders of Britain and France struck a similar note, warning that the transition towards genuine democracy had to begin immediately.

"The transition needs to be rapid and credible and needs to start now," Britain's Prime Minister David Cameron told parliament.

"We should be clear -- we stand with those in this country who want freedom, who want democracy and rights," he said, referring to the protesters in Egypt who oppose Mubarak's rule.

Sarkozy's office said that the French president also wished "that a concrete transition process begin without delay" while Ashton said the EU wanted "to see movement soon".

"We call for him to do things as quickly as possible" she added, after being asked whether the EU believed his offer to step down in September was too late.

But the call from Western powers received short shrift from the Mubarak administration which said it would only exacerbate tensions on the ground.

"What foreign parties are saying about 'a period of transition beginning immediately' in Egypt is rejected," foreign ministry spokesman Hossam Zaki said in a statement, charging that such calls "sought to inflame the internal situation in Egypt".

The prime minister of Turkey, Europe's geographical bridge to the Arab world, was much blunter, saying Mubarak should not hang around and instead must stand down immediately.

"The (Egyptian) people expect a very different decision from Mubarak," Recep Tayyip Erdogan told journalists.

"The current administration does not inspire trust so far as the democratic change wanted by the population is concerned."

While some Egyptians have said Mubarak's announcement should draw a line under the days of mass protests, others have voiced fears that he will exercise his control of the levers of power in the months ahead to fix the succession.

Carl Bildt, the Swedish foreign minister, said it was vital that no attempt should be made to limit the choice of the people.

"The Mubarak era in Egyptian politics is over," said Bildt.

"Now the decisive task will be to organize free and fair elections of Egypt's next president and to create credibility for the political development until then."

Australian Foreign Minister Kevin Rudd, visiting Athens Wednesday, said change offered more than two choices for the Arab world, represented by "an authoritarian state on one hand or an Islamist regime on the other."

"There is a third way, a democratic way for the people of this major region," he said.