BAGHDAD (Reuters) -- Followers of Shi'ite cleric Muqtada al-Sadr have marched against a pact letting U.S. forces stay in Iraq until 2011, toppling an effigy of President George W. Bush where U.S. troops once tore down a statue of Saddam Hussein.
Thousands of demonstrators chanted and waved Iraqi flags in Baghdad's Firdos Square, where U.S. forces pulled down a statue of the ousted Iraqi dictator when they took the city in 2003.
The pact, approved by both governments and now being debated rancorously in the Iraqi parliament, requires U.S. troops to leave the streets of Iraqi towns by the middle of next year and to leave the country by December 31, 2011.
U.S. forces will need Iraqi warrants to arrest people, and U.S. contractors will be subjected to Iraqi law.
Prime Minister Nuri al-Maliki obtained important concessions from the United States in months of gruelling negotiations, and has ridiculed the Sadrists for demanding a firm date for a U.S. withdrawal, only to oppose it when he delivered it in the pact.
Bush had long opposed setting a deadline. His elected successor, Democrat Barack Obama, says he will withdraw combat forces within 16 months of taking office in January.
In Firdos Square, the Sadrist protesters erected an effigy of the outgoing U.S. president, carrying a briefcase with the words "The pact of subservience and shame." They hurled bottles at the effigy, toppled it, tore it to pieces, and set it on fire.
"I am with you in evicting the occupier any way you see fit," a white-turbaned cleric read out to the demonstrators in a message from al-Sadr, to shouts of "God is Great" from the crowd.
Al-Sadr's supporters have staged several violent uprisings since 2003.
With Iraqi Army snipers peering down from the rooftops, the protesters knelt in prayer, then set off on a march chanting, "Never, never to the pact."
Senior al-Sadr aide Hazim al-Araji told Reuters: "Today is the day of Iraqi unity among Arabs, Kurds, all communities of Iraq, to reject the security pact. These people are coming out to prove the security pact is worthless."
The office of Baghdad security spokesman Major-General Qasim Moussawi said the protest took place without violent incident.
While al-Sadr's followers oppose the pact outright, other groups have expressed reservations about details.
The Iraqi government signed the accord this week and parliament is expected to vote on it next week.
Al-Maliki launched a crackdown on al-Sadr's followers earlier this year, driving his black-masked Imam Al-Mahdi Army fighters off the streets of Baghdad and cities of the Shi'ite south, which U.S. officials say gave al-Maliki new confidence in negotiations.
U.S. officials say al-Sadr himself has been in neighboring Iran since last year.
Violence in Iraq has fallen to levels unseen since the early days after the invasion. But militants are still able to carry out bomb attacks. A roadside bomb at a checkpoint in Baghdad's southerly Doura neighborhood killed three people and wounded 15 early on November 21.