WASHINGTON – The Pentagon sought Wednesday to march in step with the Obama administration's shifting war strategy as the White House considers using more counterterror strikes in Pakistan amid its doubts about adding troops in Afghanistan.

Pentagon press secretary Geoff Morrell said the U.S. and NATO commander in Afghanistan, Gen. Stanley McChrystal, would ask this week for additional American forces — a number that officials said could reach as high as 40,000 troops.

But Morrell said that request could be revised if the White House alters the military strategy it committed to six months ago. Morrell added that McChrystal's request will remain with Defense Secretary Robert Gates until the decision is made.

"There's a lot that's changed and a lot that needs to be analyzed," Morrell told reporters. "And I think it's only appropriate for the commander in chief and his national security team to discuss these developments and adjust, if necessary, accordingly."

Morrell maintained, as has the White House, that the Obama administration merely is taking a new look at how to best achieve its long-stated goal of defeating and dismantling al-Qaida, the terrorist group behind the Sept. 11, 2001, attacks.

The second-guessing comes in wake of charges of widespread fraud in Afghanistan's elections last month, and questions of whether the administration's original counterinsurgency strategy can work in a country where the government lacks credibility.

"There is a commitment on everyone's part to work this complex issue as quickly as possible, but without rushing it," Morrell said. "It is far more important that we make sure the strategy we are pursuing is the correct one and the president and his team are comfortable with it."

Earlier this year, the Pentagon began ramping up the eight-year war in Afghanistan, targeting extremist Taliban leaders to make sure the nation does not become a safe haven for al-Qaida. But White House officials now are refocusing on Pakistan, where al-Qaida leaders are believed to be hiding, by launching more missile strikes by unmanned spy planes and sending in more special operations forces.

Pakistan will not allow the United States to deploy a large-scale military troop buildup on its soil. However, its military and intelligence services are believed to have assisted the U.S. with airstrikes, even while the government publicly has condemned them.

A spokesman for the Pakistan Embassy in Washington, Nadeem Kiani, signaled that Islamabad is cool to the idea of letting the U.S. expand its CIA-led drone missions in Pakistan.

Generally, the U.S. shares the intelligence it gets from the spy planes with Pakistani leaders, but has resisted selling drones to the Pakistan for fear it could target its longtime enemy, India.

"Our position on this is well known: We would like to have this technology in our hands," Kiani said at the U.N. General Assembly in New York. That way, Kiani said, there would be no violation of Pakistan's sovereignty, "which is very dear to the Pakistani people."

On Capitol Hill, a leading Republican senator said he would support an increased focus on Pakistan, a strategy championed most prominently by Vice President Joe Biden. But Sen. Kit Bond, top Republican on the Senate Intelligence Committee, said that focus could not come at the cost of the mission in Afghanistan and should not be seen as a substitute for deploying more U.S. troops.

Democrats and Republicans largely are split along party lines on whether more troops should be sent to Afghanistan.

"While denying al-Qaida and Taliban militants sanctuary in the border regions of Pakistan is critical, a counterterrorism-only approach focusing only on one part of this regional conflict will ultimately hand victory to the world's most violent and feared terrorists," said Bond, R-Mo.

Morrell would not discuss the prospects of a new counterterror strategy in Pakistan. For now, he said, targeting the Taliban in Afghanistan "is the strategy and remains the strategy."

U.S. officials in recent weeks have said the counterinsurgency strategy endorsed by Obama in March will require more combat troops, additional trainers for Afghan security forces, and increased intelligence and surveillance forces. It also will require more helicopters and other support and equipment.

A senior Republican lawmaker in Congress recently told The Associated Press that McChrystal's troop request is expected to be as high as 40,000. The lawmaker spoke on condition of anonymity to discuss the issue more freely. Already, Obama has approved increasing the number of U.S. soldiers, sailors, pilots and Marines in Afghanistan to 68,000 by the end of this year.

The debate over the next step in the war has consumed leaders from Kabul to Brussels, where NATO is based, to Washington, where Morrell had to deny rumors that McChrystal would resign if he does not get additional troops as "just absurd, absolutely ridiculous." Gen. David Petraeus, the usually loquacious leader of U.S. Central Command that oversees operations in Afghanistan and Pakistan, refused to discuss the matter.

"There are multiple-hour meetings scheduled for the weeks that lie ahead, and folks are seized with those and are working them very hard," Petraeus told a Marine Corps University forum at the National Press Club in Washington.

McChrystal is expected to lay out "force options" — a range of several troop numbers and what can be achieved with each. Officials familiar with the process said McChrystal also will advise his top pick among the choices.

"It is not your typical request for forces," Morrell said. "This is a more analytical look at the situation and what's needed and the risks associated with certain troop levels. And there's an ultimate recommendation."