The U.S. House of Representatives voted Thursday to withdraw troops from Iraq by spring, hours after the White House released a report that called Iraq's security situation "complex and extremely challenging."
The measure passed 223-201, with 219 Democrats and four Republicans voting in favour, and 191 Republicans and 10 Democrats voting against.
It calls for a full troop withdrawal to begin within 120 days, and be fully completed by April 1, 2008.
President George Bush has vowed to veto any attempts to change the administration's war policy before September. And analysts said he has enough support to block a final Senate vote, expected next week.
The interim report also said al Qaeda will likely increase attacks in the coming months, and that the Iraqi government has made only mixed progress in its efforts to achieve political, military and economic reform.
The report said despite progress on some fronts by Nouri al-Maliki's government, "the security situation in Iraq remains complex and extremely challenging," the "economic picture is uneven" and political reconciliation is lagging.
In the interim report required by Congress, the Bush administration also said:
Syria is fostering a network that supplies as many as 50 to 80 suicide bombers per month for al Qaeda in Iraq;
Iran continues to fund extremist groups;
Iraq had not yet made needed investments to increase oil and refining output.
"The strategy recognizes that the levels of violence seen in 2006 undermined efforts to achieve political reconciliation by fueling sectarian tensions, emboldening extremists, and discrediting the Coalition and Iraqi Government," the report states.
"Amid such violence, it became significantly harder for Iraqi leaders to make the difficult compromises necessary to foster reconciliation."
The administration, however, says there are signs of hope and that more time is needed.
At a Thursday morning news conference that coincided with the report's release, U.S. President George Bush said, "I believe we should succeed in Iraq and I know we must."
In a comment clearly directed at his critics, he added: "When we start drawing down our forces in Iraq, it will (be) because our military commanders say the conditions on the ground are right, not because pollsters say it'll be good politics"
The report also said progress toward political reconciliation in Iraq was hampered by "increasing concern among Iraqi political leaders that the United States may not have a long term-commitment to Iraq."
The Iraq war, in its fifth year now, has taken the lives of more than 3,000 U.S. troops, and is costing the United States an estimated US$10 billion a month.
A second report is due in September from Gen. David Petraeus, the commander of U.S. forces in Iraq.
With a report from The Associated Press
