MPs from the secular Iraqiya bloc returned to parliament on Tuesday, ending a boycott begun last month to protest the prime minister's alleged centralisation of power, an MP from the bloc said.
"The majority of the members of Iraqiya participated in the session today," said Faiza al-Obeidi, an MP from the Sunni-backed bloc.
"We conducted the second reading of the 2012 budget and negotiated on an amnesty law" for Iraqis who have been involved in violence.
A total of 239 out of 325 MPs were present for the session, which was presided over by speaker Osama al-Nujaifi.
The "return is very significant for us due to the importance of these two laws and of the national conference," Obeidi said, referring to a conference proposed by President Jalal Talabani to resolve a political crisis that began in mid-December.
Signup to our newsletter and follow us on Facebook and Twitter!
Iraqiya began a boycott of parliament and the cabinet to protest what it charged was Prime Minister Nuri al-Maliki's centralisation of power, and it has since called for Maliki to respect a power-sharing deal or quit.
Authorities have also issued an arrest warrant for Sunni Vice President Tareq al-Hashemi, an Iraqiya member.
Maliki, a Shiite, has also said his Sunni deputy Saleh al-Mutlak should be sacked after the latter said the premier was "worse than Saddam Hussein".
Hashemi, who denies the charges, has been holed up in the autonomous Kurdish region of northern Iraq and Kurdish officials have so far declined to hand him over to Baghdad.
Iraqiya announced on Sunday that its MPs would return to parliament, somewhat easing the crisis, though it has not yet decided to return its ministers to the cabinet.
Iraqiya won the most seats in March 2010 parliamentary elections but was outmanouevred by Maliki in forming a government.