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WASHINGTON, Dec 16 (Reuters) - A White House review of President Barack Obama's Afghanistan war strategy reported on Thursday that U.S.-led forces were making headway against the Taliban and al Qaeda but warned that the gains were "fragile and reversible."
With Obama facing skepticism among lawmakers and the American public over the increasingly unpopular war, his administration's long-awaited policy assessment asserted that it was on track to meet the president's pledge to start withdrawing U.S. forces in July 2011.
But the White House tempered its optimism with caution, citing daunting challenges such as the need for further government action to combat corruption in Afghanistan and for Pakistan's "sustained denial" of safe haven for militants.
"In Afghanistan, the momentum achieved by the Taliban in recent years has been arrested in much of the country and reversed in some key areas, although these gains remain fragile and reversible," according to an unclassified summary of the review Obama had ordered by year-end.
"Most important, al Qaeda's senior leadership in Pakistan is weaker and under more sustained pressure than at any other point since it fled Afghanistan in 2001," it said.
Obama, due to speak about the findings of the Afghan review at 11:45 a.m./1645 GMT on Thursday, is under pressure to show Americans not only that the U.S. buildup in Afghanistan is paying dividends but that he is forging an exit strategy.
Despite violence across Afghanistan at its worst since 2001, the review concludes there have been "notable operational gains." It acknowledges, however, that "the challenge remains to make our gains durable and sustainable."
Independent military experts see the advances by U.S., NATO and Afghan forces as limited so far and say it is too early to tell whether the strategy will achieve much more.
Describing Pakistan as "central" to success in the region, the review said al Qaeda's leadership had been weakened but still had the ability to plot major attacks against the United States and its allies.
The report said progress in ties with Islamabad, which the United States is pushing to crack down further on militants launching cross-border attacks into Afghanistan, had been "substantial but also uneven." The White House acknowledged the need for "adjustment" in its Pakistan strategy.
But it made no mention of Afghan President Hamid Karzai, who has had often testy relations with Obama and has faced Western criticism of not doing enough against corruption.
(Reporting by Matt Spetalnick, Editing by Sandra Maler)
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