With U.S. allies likely to rebuff requests to send more combat troops to Afghanistan , many Pentagon officials want President Barack Obama to shift U.S. policy and seek NATO help only in other areas such as police training and support for democratization, defense officials said.

Obama called for more NATO combat troops while he was campaigning for the presidency. But the officials said that NATO allies are unlikely to defy the majorities of their citizens who are opposed to deeper involvement in the war, and he''d squander political capital on an almost certainly futile bid to convince them otherwise.

"The problem is that all politics is local. No constituents in those countries want to be there anymore," a U.S. defense official told McClatchy , speaking on the condition of anonymity because he wasn''t authorized to comment publicly.

Afghanistan was a major topic Wednesday of Obama''s first meeting in the Pentagon with the Joint Chiefs of Staff.

"We''re going to have some difficult decisions that we''re going to have to make" on Afghanistan , Obama said later.

The president has pledged to refocus the fight against terrorism from Iraq to Afghanistan and endorsed a request by senior U.S. commanders to increase the 30,000-strong U.S. contingent by another 30,000 troops. Most would be sent to southern Afghanistan .