A series of intertwined political crises that began with accusations that Iraq's prime minister was consolidating power have escalated into calls to unseat him, and paralysed the country's government.

"The political crisis has reached its highest level since its beginning, but it is still running within the framework of the democratic game," Iraqi political analyst Ihsan al-Shammari said.

"The country is paralysed on all levels; there is a clear political paralysis paralleled by governmental negligence and a failure of the legislative authority, while the people are disappointed and afraid of the security consequences," Shammari said.

The trouble began in earnest in mid-December, when the secular Sunni-backed Iraqiya bloc began a boycott of parliament and the cabinet over what it said was Prime Minister Nuri al-Maliki's centralisation of power.

For his part, Maliki sought to sack Sunni Deputy Prime Minister Saleh al-Mutlak, an Iraqiya member who had labelled the premier "worse than Saddam Hussein."

That month, an arrest warrant was issued for Sunni Vice President Tareq al-Hashemi, also of Iraqiya, for allegedly running a death squad.

Hashemi fled to the autonomous Kurdistan region in north Iraq, which declined to hand him over to Baghdad and then permitted him to leave on a regional tour that took him to Qatar, Saudi Arabia and Turkey.

He is now being tried in absentia in Iraq.

Kurdistan further entered the fray when its chief, Massud Barzani, launched a series of attacks against Maliki.

In April, the region stopped oil exports, claiming Baghdad has allegedly withheld more than $1.5 billion (1.2 billion euros) that Kurdish officials say is owed to foreign oil companies working in the region.

And powerful Shiite cleric Moqtada al-Sadr, whose parliamentary bloc is part of the national unity government along with Iraqiya and the Kurdish alliance, referred to the premier as a "dictator" hungry for acclaim, and accused him of wanting to postpone or cancel elections.

But Maliki opponents have now moved from merely criticising the premier to talk of actually removing him from office.

Iraqiya, which eventually returned to parliament and the cabinet, has sought to convince President Jalal Talabani to initiate a vote of no confidence in the premier in parliament, while Barzani has said he cannot work with Maliki.

"Maliki must change his policy or he will be replaced," Barzani's chief of staff Fuad Hussein said in an interview with the Rudaw news site posted on the Kurdistan region presidency's website.

"The message to Maliki is that if he can change his policy, he is welcome to do so; otherwise, he will be changed," Hussein said.

The months of acrimony have taken a toll on the functioning of the government.

Parliament has not passed significant legislation except for the budget, while other important measures such as a hydrocarbons law regulating the country's oil sector have been delayed.

And a national meeting of political leaders originally scheduled for December that was aimed at defusing the tension has yet to be held.

The crises have also had an economic impact, experts and officials say.

The "economy is retreating because of the increasing fears of investors," said Shammari.

Independent Kurdish MP Mahmud Othman added that "the problems have started influencing trade and security, and everything."

He said the heads of the political blocs "behaved as if they were in the desert," and that they needed to move from acting as leaders of parties and groups to acting like statesmen.

President Talabani warned in a statement on his website of "the seriousness of the current situation" in Iraq resulting from the political disputes, which he said is now threatening state, economic and security institutions.

He also reiterated calls for dialogue, but with no signs of reconciliation between the verbally warring parties, the acrimony seems set to continue.