This could allow all United States combat brigades “not necessary for force protection” to be out of Iraq by the first quarter of 2008, the Iraq Study Group’s report said.

The panel studying the war in Iraq presented its findings this morning to President Bush, who said he would take their ideas “very seriously” and act on them “in a timely fashion,” and then to Congressional leaders.

The report, by a 10-member commission headed by former Secretary of State James A Baker 3d and former Representative Lee Hamilton of Indiana, urges a commitment by the United States to work with Iran, Syria and other nations to bring stability to the region.

“We do not recommend a stay-the-course solution,” Baker said pointedly at a question-answer session accompanying the report’s release. “In our opinion, that is no longer viable.” Those remarks were sure to be interpreted, at least by administration critics, as a rebuke to President Bush.

Senator Harry Reid of Nevada, the Democratic leader, said the study group had done “a tremendous and historic service” by declaring that “there must be a change in Iraq, and there is no time to lose.”

But the White House could point to the commission’s refusal to advocate a quick withdrawal of American troops, an event that Hamilton said could touch off “a bloodbath” and a wider regional conflict.

Hamilton urged administration officials and lawmakers to tackle the study group’s recommendations quickly, or else, “Events in Iraq could overtake what we recommend.”

The executive summary of the report declares that its two main recommendations are “for new and enhanced diplomatic and political efforts in Iraq and the region, and a change in the primary mission of US forces in Iraq that will enable the United States to begin to move its combat forces out of Iraq responsibly.” American forces would remain after 2008, in units embedded with or otherwise supporting Iraqi troops, and in rapid reaction and special operations forces, the panel said.

But it warned that “the most important questions about Iraq’s future are now the responsibility of the Iraqis.”

The White House spokesman, Tony Snow, speaking to reporters after the president’s briefing, emphasised that the report’s 79 recommendations do not include either a firm timetable or a call for an immediate withdrawal.

“There is nothing in here about pulling back militarily,” he said.

But the report seems to hold little other comfort for Bush, describing the situation in Iraq as “grave and deteriorating,” and calling him to pursue moves he has resisted, including making diplomatic overtures to Iran and Syria. It also recommends that the administration “reduce its political, military or economic support for the Iraqi government” if it “does not make substantial progress toward the achievement of milestones on national reconciliation, security and governance.”

Baker and Hamilton wrote in a joint letter accompanying the report that “there is no magic formula to solve the problems of Iraq.”

Among other things, the report recommended:

Immediately launching a diplomatic offensive “to build an international consensus for stability in Iraq and the region,” including “all of Iraq’s neighbours.”

An effort to engage Iran and Syria “constructively.”

The Iraqi government should increase the number and quality of its army brigades.

The US should significantly increase the number of military personnel embedded with or supporting Iraqi units.

The US could move most combat troops out of Iraq by early 2008, leaving a smaller force to focus on rapid-reaction operations.

-JOHN O’NEIL & BRIAN KNOWLTON