Members of the Sunni Muslim-backed Iraqiya bloc boycotted Iraq's parliament and cabinet on Tuesday, accusing Shi'ite Prime Minister Nuri al-Maliki's bloc of governing alone in a power-sharing coalition that was supposed to ease sectarian tensions.
The political turmoil that has stoked concern of renewed sectarian strife erupted as the last U.S. troops were leaving in mid-December, when Maliki sought the arrest of a Sunni vice president and asked parliament to remove Maliki's Sunni deputy.
Iraq is still plagued by a lethal Sunni insurgency and Shi'ite militias nearly nine years after the invasion that ousted Saddam Hussein.
Maliki's moves against Vice President Tareq al-Hashemi and Deputy Prime Minister Saleh al-Mutlaq and a spate of bombings that have killed at least 72 people in mainly Shi'ite areas of Baghdad have only deepened the fears.
Cross-sectarian Iraqiya, which won the most seats in parliament in the 2010 election with heavy Sunni support, announced the boycott after accusing Maliki's Shi'ite-led government of concentrating power.
"We are still refusing to go inside, boycotting the sessions," Iraqiya lawmaker Nada Ibrahim said outside the chamber where parliament met for the first time since the crisis erupted. "The whole Iraqiya bloc."
"There is no real power-sharing. Things have been governed by one group. This is not what we were waiting for in the new Iraq, democratic Iraq."
Reporters are not allowed into the parliament chamber but a number of lawmakers from Iraqiya and other blocs said most Iraqiya members were absent, although Iraqiya leader and prominent Sunni Osama al-Nujaifi presided as speaker.
The inclusion of Iraqiya in the governing coalition was considered crucial to prevent a slide back into the kind of sectarian violence that killed thousands and carried Iraq to the brink of civil war in 2006-7.
Many Sunnis have complained of being sidelined in the political process since Saddam was ousted and majority Shi'ites took power. Sunni-dominated provinces have pushed for more autonomy from the central government.
But despite the angry rhetoric and sectarian overtones, Iraqi officials are working behind the scenes to cool tensions. The blocs appear to have agreed in principle to hold a national conference this month to work out differences, and to let the courts deal with allegations that Hashemi ran death squads.
All eight Iraqiya cabinet ministers, including Finance Minister Rafie al-Esawi, also skipped a cabinet meeting on Tuesday, Cabinet Secretary Ali al-Alaq said.
"None of the Iraqiya ministers attended, and the cabinet decided to consider them 'on leave' and to appoint acting ministers until they join in again," Alaq said.
Iraqiya lawmaker Wihda al-Jumaili said the boycott would continue until the government ended an arrest campaign against government opponents, transferred Hashemi's case to a "neutral" province and met other demands.
"We are sure that he (Hashemi) is innocent. The constitution gives the right to every Iraqi citizen to have a fair and honest trial," Jumaili said. "And if the trial is held in Baghdad, it won't be a fair trial."
The Iraqiya boycott failed to delay parliament, which had enough members for a quorum.
"This is an important step which represents a respect for the constitution and a respect for the Iraqi people's interest," said Adnan al-Shahmani, a member of Maliki's State of Law bloc.
If the boycott continues, Maliki could turn to Kurdish lawmakers and Iraqiya dissidents to govern without the Sunni-backed bloc. Twelve lawmakers have left Iraqiya in recent weeks.
In addition to the boycott, Kurdish lawmakers stormed out of the chamber, angry that a member of State of Law accused Iraq's Kurdish president, Jalal Talabani, of illegally harbouring Hashemi, who took refuge in semi-autonomous Kurdistan. The Kurds returned after a brief walkout.