Baghdad, Iraq ? Thousands of Sunni Muslims, uneasy at the prospect of losing their position in Iraqi society to the Shiite majority, staged their first show of force Friday since the fall of President Saddam Hussein’s government, marching through the streets of Baghdad to protest the U.S. military occupation and to demand a Muslim state without distinction between Sunnis and Shiites.

The impassioned demonstration would have been unthinkable under Saddam, who banned unsanctioned rallies. In any case, it would have been unnecessary; Saddam accorded disproportionate influence to his fellow Sunnis, who traditionally have held the upper hand in Iraq’s official, economic and social life. In a new, post-Saddam Iraq, the marchers seemed to say, such cleavages should be set aside in favor of a nation unified around shared Islamic faith.

“No Sunni. No Shiite. Only One Islamic Nation,” proclaimed one painted-cloth banner. “Iraq must be ruled by its people,” read another.

In the nine days since U.S. tanks took control of Baghdad, newly emboldened Shiites have engaged in public acts of religious expression that long were banned by the former Iraqi leader out of a desire to exert social control and promote the secular philosophy of his Baath Party.

The behavior of Shiites, who make up about 60 percent of Iraq’s 24 million people, has provoked quiet but intense concern among Sunnis and the even smaller Christian minority, who all fear they will be marginalized in a new government if it reflects the country’s demographics.

‘Weeks rather than months’

The protesters, led by a well-known Sunni scholar, began their march Friday at one of Baghdad’s largest Sunni mosques after prayers. They called on U.S. troops to leave quickly and for a new government to be based on Islamic laws. Although those demands appeared to reflect growing frustration with the pace of American aid and reconstruction programs in Iraq, they also were overtures to Shiite leaders, who have made similar requests, and an indication of how Islamic politics is starting to fill the political vacuum left by Saddam’s downfall.

Among the signs carried by some of the approximately 10,000 marchers were two claiming to represent the Muslim Brotherhood, the largest Islamic activist movement in the Arab world. It was the first time the Brotherhood, a Muslim revivalist group that is banned in Egypt and Syria, has appeared on the public stage in Iraq.

Shortly after the protest, Ahmed Chalabi, leader of a U.S.-backed group that opposed Saddam, predicted that an interim Iraqi government would take over most government functions from the U.S. military in “a matter of weeks rather than months.” Chalabi, who heads the Iraqi National Congress, did not specify how the interim government would be selected, but he said he will not be a candidate to lead the country.

Power grab beginning?

Now, with the old system gone and uncharted political territory ahead, Shiites have begun expressing themselves in ways they could not before, holding large rallies for revered leaders and hoisting trademark green flags. Many Sunnis said those actions are the first step in a power grab that could leave them politically and socially marginalized.

As a consequence, Sunni leaders have been touting the concept of religious harmony — a subtle message aimed at winning over Shiites.

“We fear that sectarianism will be exploited by our enemies,” said Ahmed Kubeisi, a prominent Sunni cleric who had been a critic of Saddam. said in a sermon before the march. “Both Sunnis and Shiites should work for unity. We are all Muslims.”

Kubeisi lashed out at both Saddam and Bush, criticizing the previous government as corrupt and the United States as interested only in Iraq’s oil. He argued that U.S. troops should leave quickly and Iraqis should be free to lead themselves.

“You are the masters today,” Kubeisi said of the U.S. troops here. “But I warn you against thinking of staying. Get out before we force you out.”

In neighboring Saudi Arabia, the foreign ministers of six countries that border Iraq met for their first postwar summit, saying they expected to conclude the meeting by jointly denouncing the prospect of a U.S. military occupation of Iraq, even short-term. The ministers also criticized U.S. diplomatic pressure on Syria, which the Bush administration has accused of harboring fugitive members of Hussein’s government and possessing chemical weapons.

In an opening address to the foreign ministers of Turkey, Iran, Syria, Kuwait and Jordan, the Saudi foreign minister, Prince Saud Faisal, said threats against Syria would “lead to a vicious cycle of wars and turmoil.”