Baghdad  - An Iraqi parliament session on Wednesday to discuss a security pact between the United States and Iraq was adjourned for a day after lawmakers loyal to Shiite cleric Moqtada al-Sadr disrupted the session, Dubai-based channel al-Arabiya reported.

The 275-member house should vote on the so-called Status of Forces Agreement (SOFA) before November 24, according to the agreement signed by Iraqi Foreign Minister Hoshyar Zebari and US Ambassador to Iraq Ryan Crocker on Monday.

The agreement needs parliamentary approval before it can be signed into law by the US and Iraqi presidents.

Sadrists, loyal to the anti-US cleric al-Sadr, holds 30 seats in the parliament, and are the most vocal critics of the deal.

The agreement between Washington and Baghdad sets the legal basis for the future presence of US troops in Iraq after a United Nations Security Council mandate expires at the end of the year.

Under the pact, the deadline for the complete withdrawal of US troops - currently standing at more than 140,000 - would be December 31, 2011.

A senior US official said the US would withdraw its troops from Iraq if the security pact was not signed, Iraq's semi-official al- Sabah newspaper.

"The United States will withdraw its forces from Iraq and refuse to approve an extension of the UN Security Council mandate if the treaty is not signed," David Satterfield, senior advisor to the US secretary of state and the country's Iraq coordinator, told the paper.

Satterfield met with Iraqi groups opposing SOFA to try to persuade them to support it, the newspaper reported.

Separately, Iraqis demonstrated in the cities of Tikrit and Hillah in support of the pact.

In Tikrit, in central Iraq, demonstrators chanted support for Iraqi Premier Nuri al-Maliki, who recently urged Iraqis to back the pact in a nationally televised address.

"When our (Iraqi) government makes a mistake we stand against it, but when it is going in the right track we should support it," one demonstrator told Deutsche Presse-Agentur, dpa.

The demonstration in Hillah, about 85 kilometres south of Baghdad, took place earlier with more than 5,000 Iraqis including clan chiefs and students, witnesses told dpa.

Chanting slogans urging the Iraqi government to sign the security agreement, demonstrators carried flags and signs reading: "Together for the withdrawal of foreign troops from Iraq" and "With heart, with blood, we save you, Iraq."

The demonstrators walked to the Hillah city council surrounded by hundreds of Iraqi police and soldiers.

Meanwhile, at least six people were injured in separate bomb blasts Wednesday.

Five people were injured by a bomb in central Baghdad's Oqbah bin Nafaa square, and a soldier was injured in the northern city of Mosul by a bomb attack on an army patrol, security sources told the Voices of Iraq (VOI) news agency. (dpa)