By Tom Perry and Sarah Mikhail
CAIRO (Reuters) - Egypt's new prime minister told thousands of demonstrators in Tahrir Square on Friday he was committed to the goals of their revolution and promised to take to the streets in protest if he could not deliver.
Egypt's military rulers designated Essam Sharaf prime minister on Thursday, meeting demands for the removal of Ahmed Shafiq in a step seen as an attempt to soak up anger that has fueled protests since President Hosni Mubarak stepped down.
Mubarak, toppled on February 11 by a wave of mass demonstrations, appointed Shafiq in his last weeks in the presidency. The military council to which Mubarak handed power is now charting the country's course toward elections.
They have set a March 19 date for a referendum on constitutional amendments that will open up competition for the position of the presidency held by Mubarak for three decades, the government announced on Friday.
The constitutional reforms, a milestone on what Egyptians hope is their road to democracy, will stop any president from serving more than two consecutive four-year terms -- a major change that will serve as an example in a region of autocrats.
Analysts say the military, keen to avoid more protests, appears to have become more responsive to the demands of reformists still pushing for deeper changes and worried about a "counter revolution" by remnants of Mubarak's administration.
Sharaf's name had been recommended as a candidate for the post of prime minister by leading reformist Mohamed ElBaradei. Sharaf also was supported by youth activists demanding change.
"I am here to draw my legitimacy from you. You are the ones to whom legitimacy belongs," Sharaf told thousands of people who had gathered in Tahrir Square -- the epicenter of the protest movement that toppled Muabrak.
"I have been entrusted with a heavy mission and need patience, will and resolve," he said.
"The mission that I am trying to realize, with all my heart, is your goals," he continued, adding that the day when he could not, he would join the protesters in the square.
"A GOOD START"
He addressed protester demands for the reform of security services whose reputation for brutality had helped fuel the revolt against Mubarak. The police should be in the service of citizens, Sharaf said.
"Take the oath, take the oath, take the oath," chanted the crowd, urging Sharaf to take the oath of office in front of them. He declined to do so before being carried away on protesters' shoulders.
Sharaf's appearance in Tahrir Square showed "political intelligence," said Nabil Abdel Fattah, a political analyst at al-Ahram Center for Political and Strategic Studies.
"It is a good start but whether the masses will accept him still needs time," he said. Sharaf is expected to make changes to the cabinet in which the ministries of foreign affairs, the interior and justice remain in the hands of Mubarak appointees.
Ayman Nour, an opposition figure, said Sharaf was "on the right track."
"But we wished he had spoken about his agenda and his plans about emergency law and the state security establishment," Nour, who ran against Mubarak for the presidency in 2005, said.
Egypt's reform movement wants the state of emergency lifted -- something the military council has promised to do before elections. The military council is also facing calls for a change to the timeline it has set for elections.
The military wants to hand power back to an elected civilian government within six months and has indicated that a parliamentary election will come ahead of a presidential one.
Reformists say a presidential election should come first with more time before parliamentary elections to allow political life to recover from decades of suppression by Mubarak.
"I think that possibly when the military took this on they had hoped it would be a one, two, three: 'You get your amendments, we'll have these two elections and we're gone,'" a Western diplomat said.
"But it seems the people of Egypt need more, so bit by bit, we are seeing the Supreme Council of the Armed Forces having to grapple with this."
(Additional reporting by Yasmine Saleh and Marwa Awad; Writing by Tom Perry, editing by Peter Millership and Michael Roddy)