President Bush said he supports a $120 billion Iraq war spending bill on track to pass through Congress today, ending weeks of wrangling with congressional Democrats on how long US troops should stay.
The bill funds the war to September as Mr Bush wanted and does not set a date for troop withdrawals.
In exchange for dropping restrictions on the military, Mr Bush agreed to some $17 billion in spending added by Democrats to fund domestic and military-related projects.
"By voting for this bill, members of both parties can show our troops and the Iraqis and the enemy that our country will support our service men and women in harm's way," Mr Bush said in a Rose Garden news conference.
Mr Bush said this summer will be a critical time for his troop buildup strategy in Iraq and predicted heavy fighting in the weeks and months ahead.
Faced with demands to make progress in Iraq by September from Democrats and many Republicans, Mr Bush that the last troops in a 30,000-troop buildup should be in place by mid-June, and said "This summer is going to be a critical time for the new strategy."
"We expect heavy fighting in the weeks and months" ahead, Bush said. He said more American and Iraqi casualties should be expected.
Asked how long he believed he could sustain the policy without significant progress on the ground, Mr Bush noted that the US commander in Iraq, General David Petraeus, is to report back on the effects of the new strategy at the end of the summer.
Democrats said they were disappointed with the deal.
"I hate this agreement," said Representative David Obey, chairman of the Appropriations Committee.
Mr Obey said the deal was the best that Democrats could do because "the White House is in a cloud somewhere in terms of understanding the realities in Iraq."
The bill includes the nearly $100 billion that President Bush requested for military and diplomatic operations in Iraq and Afghanistan as well as billions in domestic spending, including $6.4 billion in hurricane relief and $3 billion in agricultural assistance.
Republicans were unhappy about the added domestic spending, but said they were relieved the final measure did not attempt to set a timetable on the war.
"We cannot and will not abandon the Iraqis to be butchered by these terrorists in their midst," said Representative David Dreier.
"And we cannot and will not abandon our mission just as real progress is starting to be made."
While the measure does not include a timetable on the war, it does threaten to withhold US aid dollars for Iraq if Baghdad fails to make progress on political and security reforms. The president, however, could waive that restriction.
Mr Bush said Iraq's ability to meet the benchmarks outlined in the bill would be difficult.
"It's going to be hard work for this young government," he said. "After all, the Iraqis are recovering from decades of brutal dictatorship."
The hefty spending bill has become a lightning rod for political attacks on Mr Bush and his handling of the deeply unpopular war, which has killed more than 3,400 US troops and cost more than $300 billion.
But it also has exposed a sharp divide among Democrats on how far Congress should go to end the war.