WASHINGTON -- New U.S. intelligence reports paint a bleak picture of the security conditions in Afghanistan and say the war cannot be won unless Pakistan roots out militants on its side of the border, according to several U.S. officials who have been briefed on the findings.

The reports, one on Afghanistan, the other on Pakistan, could complicate the Obama administration's plans to report next week that the war is turning a corner. U.S. military commanders have challenged the new conclusions, however, saying they are based on outdated information that does not take into account progress made in recent months, says a senior U.S. official who is part of the review process.

The analyses were detailed in briefings to the Senate Intelligence Committee this week and some of the findings were shared with members of the House Intelligence Committee, officials said.

All the officials interviewed spoke on condition of anonymity to discuss the classified documents.

The reports, known as National Intelligence Estimates, are prepared by the Director of National Intelligence and used by policymakers as senior as the president to understand trends in a region. The new reports are the first ones done in two years on Afghanistan and six years on Pakistan, officials said. Neither the Director of National Intelligence nor the CIA would comment on either report.

The new report on Afghanistan cites progress in "inkspots" where there are enough U.S. or NATO troops to maintain security, such as Kabul and parts of Helmand and Kandahar provinces. Much of the rest of the country remains Taliban-controlled, or at least vulnerable to Taliban infiltration, according to an official who read the executive summary.

The report contains public opinion polling that finds Afghans are ambivalent, as willing to cut a deal with the Taliban as they are to work with the Americans, the official said.

It also shows U.S. efforts are lagging to build infrastructure and get trained security forces to areas where they are needed, the official said. And it says the war cannot be won unless Pakistan is willing to obliterate terrorist havens in its lawless tribal areas bordering Afghanistan.

The new report on Pakistan concludes that the Pakistani government and military "are not willing to do that," says one U.S. official briefed on the analysis.

The document says Pakistan's government pays lip service to cooperating with U.S. efforts against the militants, and still secretly backs the Taliban as a way of hedging its bets in order to influence Afghanistan after a U.S. departure from the region.

In describing the Afghanistan report, military officials said there is a disconnect between the findings, completed in recent weeks, and separate battlefield assessments done by the war commander, Gen. David Petraeus, and others that contain more up-to-date and sometimes more promising accounts.

A military official familiar with the reports said the gloomier prognosis in the Afghanistan report became a source of friction as a preliminary version was passed among government agencies.

Marine Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, acknowledged the contrast between the Afghan estimate and Petraeus' reports.

"It's a very disciplined, structured process, so it's got a cutoff date that's substantially earlier in the game than, say, the military review," Cartwright said in a recent interview.

He said officials will have to grapple with whether intelligence and battlefield reports are starting to diverge or whether the gloomier intelligence analysis is "more an artifact of time. Those are the questions that we'll have to work our way through and either feel comfortable about or not feel comfortable about."

While the intelligence assessments show the Obama administration may still be struggling to change Pakistani behavior, former Obama war adviser Bruce Riedel disputes the hypothesis that the war cannot be won if Pakistan does not close terrorist sanctuaries.

"If the U.S. continues to strengthen the Afghan state and army, that may force Pakistan to reconsider its support for the Taliban," said Riedel, a former CIA officer, and author of the forthcoming book, "Deadly Embrace: Pakistan, America and the Future of the Global Jihad."

Amrullah Saleh, who led Afghanistan's spy agency from 2004 until early this year, told a Washington conference Thursday that the key to defeating the Taliban is cutting off their support from Pakistan. "Demobilize them, disarm them, take their headquarters out of the Pakistani intelligence's basements," Saleh said.

Pakistan denies supporting the Taliban.