The National Concord Front, the main Sunni bloc with 44 MPs in the 275-member parliament, walked out of the assembly, saying it would return after al-Dulaimi himself comes back to the legislature.
The Iraqi army said on Thursday it found car bombs near al-Dulaimi's Baghdad offices in the Hail Adel neighbourhood.
After the Iraqi military detonated the car bombs, US and Iraqi officials said the keys to the vehicle were found on one of al-Dulaimi's bodyguards.
Maki al-Dulaimi, his son, and about 30 other people were arrested on Friday, while al-Dulaimi said he was put under "confinement" in his home.
"We announce our boycott of the parliament until Adnan al-Dulaimi returns to the assembly today or tomorrow," the bloc's Abdul Karim al-Samarraie told the assembly.
"When I went to meet him I was stopped and told that he is under house arrest. This is a violation of the rights of an MP who wants to come to the parliament."
Ali al-Dabbagh, the Iraqi government spokesman, denied that al-Dulaimi was under house arrest.
"What is being said about house arrest is not true. It is only protection given to Dulaimi until the situation is clear," he told Al-Iraqiya, the state television.
In other major developments on Saturday, dozens of suspected al-Qaeda fighters bombarded a Shia village in Diyala province with mortar rounds, then stormed the streets, killing at least 13 Iraqis, torching homes and forcing about 500 families to flee, police said.
Some villagers fought back, leaving three fighters dead in the heart of one of Iraq's most violent regions.
|US and Iraqi troops have been conducting joint raids against alleged al-Qaeda hideouts [AFP]|
The armed offensive on Dwelah, about 75km north of Baghdad, began about 6:30am with the mortar rounds, then 50-60 suspected al-Qaeda fighters streamed in and opened fire, a police officer said.
Among the 13 dead were three children and two women, the officer said, speaking on condition of anonymity.
Elsewhere in Diyala, Iraqi officials said US and Iraqi soldiers, police and members of a local tribe freed four villages from al-Qaeda control, killing 10 fighters and arresting 15 in a two-day operation that ended on Saturday.
Among the weapons and ammunition seized were 100 barrels of TNT, according the provincial army and police headquarters.
The US military said it could not immediately confirm the report.