WASHINGTON - President Barack Obama told congressional leaders on Tuesday his decision on a new Afghan war strategy would not make everyone happy, while Republicans urged him to heed his military commander's call for more troops.

Obama summoned key Democratic and Republican lawmakers for a meeting at the White House to hash out their views on how to overhaul strategy in the eight-year war, where the military says the Taliban has the momentum in the unpopular conflict.

Obama told the meeting his decision, to be announced in the coming weeks, would be based on what he thought would be the best way to prevent future attacks on the United States and its allies, a U.S. official said.

He also made it clear that his decision won't make everybody in the room or the nation happy, but underscored his commitment to work on a collaborative basis, the official said.

At the heart of the debate within the Obama administration is whether it would be best to send more troops to Afghanistan and work to earn the trust of the Afghan people or to more narrowly focus the war effort using airstrikes against al Qaeda targets.

Republican Senator John McCain warned Obama against half measures and urged him to implement a plan by the commander of U.S. forces in Afghanistan, General Stanley McChrystal, who wants as many as 40,000 more troops and trainers to fight the war.

I am very convinced that General McChrystal's analysis is not only correct but should be employed as quickly as possible, McCain told reporters after the 90-minute meeting.

There is no middle ground, said McCain, who lost the election to Obama last year.

Democrats countered that Obama was being responsible by taking his time to decide on a strategy in Afghanistan.

We all realize the important decision the president has to make. Eight solders were killed on Sunday, one of them was from Reno, Nevada, said Senate Majority leader Harry Reid, who represents Nevada.

PUBLIC UNEASE

Obama's meeting with lawmakers follows a brutal firefight in eastern Afghanistan last weekend in which eight U.S. troops were killed and NATO forces said more than 100 militants died.

There is growing public unease over the war as well as skepticism among members of Obama's own party who question whether it is worth sending in more troops.

There were some on the other side of equation, who indicated that perhaps the political will was not there in terms of the people of this country to support another mission, said Eric Cantor, the No. 2 Republican in the House of Representatives.

Republican Senator Judd Gregg said there was no consensus in the meeting about what should be done in Afghanistan and House of Representatives Speaker Nancy Pelosi, a Democrat, spoke of the diversity of opinion in the room.

The debate over what to do in Afghanistan has been complicated by the uncertain outcome of the country's August election which was marred by widespread allegations of fraud.

Incumbent President Hamid Karzai is expected to win and Pelosi said there were questions whether his government could perform in a way that was not corrupt. Do we have an able partner in President Karzai? she asked.

While one option is to send additional troops, the administration is also looking at whether scale back the mission and focus on striking al Qaeda cells in neighboring Pakistan, an idea backed by Vice President Joe Biden.

The White House and Defense Secretary Robert Gates have sought to tamp down talk of a third option -- to withdraw from Afghanistan entirely.

The president reiterated that we need this debate to be honest and dispense with the straw man argument that this is about either doubling down or leaving Afghanistan, said the U.S. official.

Leaving Afghanistan isn't an option, White House spokesman Robert Gibbs said earlier.

Obama's review could still take several weeks and a meeting with his national security team on Wednesday will focus largely on Pakistan, said Gibbs.

Pakistan's Foreign Minister Shah Mehmood Qureshi was in Washington on Tuesday for meetings with Secretary of State Hillary Clinton as well as lawmakers who hold the purse strings for future U.S. aid to Pakistan.

Qureshi urged the United States to make a long-term commitment to his country, Afghanistan and the region.

The inconsistency of the past has to be kept in mind and we have to build on learning from the mistakes of the past, Qureshi said at a joint news conference with Clinton.

Last week, Congress passed a bill to allocate $1.5 billion a year in nonmilitary aid to Pakistan over the next five years as part of the Obama administration's strategy to fight extremism with jobs and reconstruction.

(Additional reporting by Caren Bohan, Steve Holland, Arshad Mohammed, Susan Cornwell, Tabassum Zakaria and Donna Smith in Washington and Peter Graff in Kabul. Editing by Chris Wilson)

Pakistan Afghanistan Eric cantor Nancy Pelosi