Radical cleric Moqtada al-Sadr pulled his six ministers out of Iraq's beleaguered coalition government on Monday as he pushed his demand for a rapid withdrawal of US troops from the country.
The Shiite hardliner -- who has not been seen in public since October -- was angered last week when street protests failed to persuade Prime Minister Nuri al-Maliki to set a timeline for American forces to go home.
Sadr's bloc is the largest single political group in Maliki's fragmenting coalition, but the prime minister will be able to cling to power if he keeps the support of smaller Shiite and Kurdish groups.
Lawmaker Nassar al-Rubaie from Sadr's movement, flanked by allies from his 32-strong parliamentary bloc, announced the withdrawal at a Baghdad news conference, reading a statement from the cleric.
"The six ministries shall be handed over to the government itself in the hope that this government will give these responsibilities to independent bodies who wish to serve the interest of the people and the country," it said.
Rubaie explained the reasons behind the move.
"The main reasons are the prime minister's lack of response to the demands of nearly one million people in Najaf asking for the withdrawal of US forces and the deterioration in security and services," he said.
On April 9, a rally organised by the group saw huge crowds of Shiites gather in the holy city of Najaf to demand the withdrawal of foreign troops from the war-ravaged country.
The number of protesters was disputed, with the US military reporting around 15,000 and Iraqi officials hundreds of thousands.
Maliki welcomed the Sadr boycott, saying it will help speed up his much-awaited cabinet reshuffle that would bring in "efficient ministers."
In a statement, Maliki said Sadr's decision gave him "the task of selecting efficient ministers for the posts formerly occupied by ministers from the Sadr bloc, without reference to sectarian power-sharing policy.
"The prime minister appreciates the support of the Sadr bloc to the political process but stresses that a sectarian sharing policy was not the right option to help Iraq in the face of challenges and difficulties."
Maliki also stuck to his refusal to offer a timeline for a US withdrawal.
"The issue of the withdrawal of multinational forces depends on the readiness of our armed forces to take charge of security in all provinces," he said reiterating his earlier stand.
Maliki's adviser Mariam al-Rayis, said that by boycotting the government the Sadr bloc was emerging as a useful opposition voice in the parliament.
"We need to have real opposition from outside the government. This is a great beginning. The prime minister needs real opposition that can act as a watchdog inside the parliament," she said.
In recent months there have been clashes between fighters from Sadr's Mahdi Army militia and Shiite-led security forces, while US troops have rounded up many militia leaders in raids around the country.
The young cleric -- he is thought to be in his early thirties -- is the wild card in Iraqi politics, with more power to disrupt than to encourage the country's small, faltering steps towards national reconciliation.
He has not been seen in public since last October, and US commanders believe he is hiding out in Iran, a claim denied by his supporters.
Despite this apparent dispute between the former allies -- Sadr's votes ensured the prime minister's election -- some analysts said Maliki could use the defection to strengthen his own position.
"He will use this to exert pressure on the Americans to prepare for their withdrawal and intensify the training of the Iraqi troops," Harb said.
In Washington, White House spokeswoman Dana Perino played down the importance of Sadr's move, saying: "Coalitions in those types of parliamentary democracies can come and go.
"If the Sadrists were to leave the government ... that does not mean that Maliki loses his majority. I think that's an important thing to remember."
In 2004, Sadr launched two bloody rebellions against US forces, but since then has preferred to be seen as part of Iraq's troubled political process.
The International Crisis Group's Iraq expert, Joost Hiltermann, warned that Sadr's movement remains unpredictable but said the Shiite firebrand was gambling on being able to wait out his US foes.
"Sadr does not want to restart a fight with the Americans as there is a feeling that they will go away next year. He wants to wait it out. But he has to consolidate himself," Hiltermann said.
On Monday insurgents continued their attacks with at least 19 people killed in northern Iraq, including 13 Iraqi soldiers who were shot dead by gunmen.
The US military also announced the deaths of two more soldiers in Baghdad on Monday, taking its toll to 45 in April alone and to 3,299 since the March 2003 invasion, according to Pentagon figures.
Ten employees of the education ministry were kidnapped while on their way to Baghdad from the oil city of Kirkuk, police said.
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