WASHINGTON, 8 May 2007 — President Bush has mobilized his administration, including his top general in Iraq, in a major push to win more time and money for his war strategy. But one crucial voice has been missing from the chorus: US Defense Secretary Robert M. Gates.

In fact, Gates’ recent comments seem to run counter to the message from the White House. During a recent trip to the Middle East, Gates told the Iraqi government that time was running out and praised Democratic efforts in the US Congress to set a timetable, saying it would help prod the Iraqis. He reiterated that point during a meeting with reporters last week.

A spokesman for Gates insisted there is no distance between the defense secretary’s thinking on the timetable for Iraq and views held by White House or Army Gen. David H. Petraeus, commander of US troops in Iraq.

But his warnings to Iraqi Prime Minister Nuri Al-Maliki are just the latest indications from Gates that he believes the window of opportunity for the administration to get Iraq right is closing sooner rather than later.

Any determination by Gates that time is running out on the current plan could severely complicate the administration’s strategy this summer, a prospect that has begun to worry some backers of the so-called troop “surge.’’

“I believe Gates is on a completely different page than President Bush and Gen. Petraeus,’’ said a former senior Defense official who has supported the buildup. “He wants to see some results by summer, and if he doesn’t see those results, he seems willing to throw the towel in.’’

Gates was a member of the bipartisan Iraq Study Group, the blue-ribbon commission that recommended combat troop withdrawals in its report last year. Gates did not sign the report; he has said that formal deliberations did not start until after he left for the Pentagon. But several people who worked on the report said Gates was closely involved in early drafts and would have supported its eventual conclusions.

“Knowing how that group got along and how we shared our views, there remains no question in my mind that Bob Gates, had he not become secretary of defense, would have supported those recommendations,’’ said Leon Panetta, a former White House chief of staff and a member of the Iraq panel.

Gates came to the Pentagon last year vowing unvarnished assessments of progress in Iraq, and established a reputation on Capitol Hill for speaking frankly. As a result, he has become a rare trusted administration voice on Iraq policy, unencumbered by the baggage of the war’s initial planning and execution.

But since taking over from the divisive Donald H. Rumsfeld in December, Gates largely has kept his views on the surge to himself. At Bush’s direction, Gates spent his first weeks at the Pentagon gathering information to recommend a new course. But administration officials have acknowledged since that the new course already had been set, and Gates became its chief manager.

In that role, he has refrained from praising the strategy and is exploring backup plans in case it fails. He hopes to begin troop reductions this year and has ordered planners to keep funding for the build-up out of next year’s budget, an indication he wants the increase to end in 2007. And while he sides with the administration against hard deadlines, he parts ways with the buildup’s top backers by recognizing value in the debate over timetables.

Gates’ sharpest public difference with supporters of Bush’s surge strategy has been over the question of how long the buildup should last before undergoing a thorough assessment.

Gates has insisted for much of the year that the current Baghdad security plan be evaluated this summer — barely two months after all five of the surge brigades are in place. And Gates occasionally has scolded senior officers who have suggested otherwise.

Army Maj. Gen. William Caldwell, the chief military spokesman in Baghdad, suggested in recent weeks that signs of progress might have to wait until the fall. Gates responded harshly.

“I was a little disturbed, frankly, to hear that one of our military officers — and I don’t know who it was — saying it will be fall before we have some good idea,’’ Gates told a congressional hearing, unprompted by any question about timing.

Gates eventually gave way after Bush himself announced that he would give Petraeus until September.

Nonetheless, Gates’ views worry military officials who support the troop increase. One senior military officer argued that rather than talking about time running out, Gates and the Pentagon ought to be trying to buy more time for the new strategy.

“If we cannot practice a little strategic patience right now,’’ said the officer, “we might as well pull out.’’

Added a military analyst who has consulted for the Pentagon: “(Gates) seems to be off message and I do not know why. I don’t know if Gates thinks the war can be won. He has said it can, but I am not 100 percent sold that he believes it, and that is a real problem.’’

Some experts, former officials and military officers interviewed for this article spoke on condition of anonymity when discussing Gates’ views of the war.

Bryan Whitman, a Pentagon spokesman, said Gates has been clear that he believes true reconciliation and progress in Iraq will take time. “Gen. Petraeus and Secretary Gates are of like minds on this matter,’’ Whitman said. “To suggest that some how he has a different view... on the strategy is wrong, it’s uninformed, and it’s mischievous to suggest so.’’