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Two new classified U.S. intelligence assessments on the war in Afghanistan reportedly say there is a limited chance of success unless Pakistan hunts down insurgents operating from havens on its Afghan border.

The National Intelligence Estimates offer a more negative assessment than a review of the U.S. war strategy that the Obama administration is set to unveil on Thursday.

The intelligence reports -- one on Afghanistan and one on Pakistan -- say that although there has been progress in the war, Pakistan's unwillingness to shut down militant sanctuaries in its lawless tribal region remains a serious obstacle, The New York Times reported late Tuesday.

The Times said the findings of the intelligence community were provided to some members of the Senate and House Intelligence Committees last week and were described by a number of U.S. officials who read the executive summaries.

U.S. military commanders and senior Pentagon officials have already criticized the reports as out of date and written by Washington analysts who have spent little time in the war zone, the newspaper said.

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In a detailed preview of statements President Barack Obama will make Thursday, White House press secretary Robert Gibbs said the yearlong review of Obama's war plan will, essentially, offer no surprise. The president plans to stick with his pledge to start drawing home troops next summer after ordering one year ago that 30,000 more troops be sent to Afghanistan to blunt the Taliban's momentum. The goal of coalition forces is to shift control to Afghan security forces by the end of 2014.

A summary of the classified war report is expected to be released Thursday, when Obama will speak about the effort from the White House.

The review is expected to cite progress in combating the Taliban in Afghanistan, degrading senior Al Qaeda leaders, and improving cooperation with the Pakistani government, Gibbs said. It will cite big challenges that still hamper the war effort, including Afghanistan's capacity to build up its own basic services and security forces, and the ability of militants to reside in Pakistan and undermine security in Afghanistan -- "there's absolutely no doubt about that," Gibbs said.

Obama will not announce the pace or scope of the troop drawdown, Gibbs said; that is to be determined the coming months.

But he said: "I think we are on course for the July 2011 date."

There are about 100,000 U.S. troops in Afghanistan.

Gibbs said the report will leave no doubt that the war is going better now than it was before Obama increased the U.S. presence in Afghanistan.

It has also grown more deadly as the fighting intensifies. More than 680 international troops, including more than 470 Americans, have been killed in 2010, making it the deadliest year of the war. Hundreds of Afghan civilians have also died, most as a result of Taliban attacks.

The review is also expected to describe the emergence of two separate fights: a textbook battle to counter insurgents in the south of Afghanistan and a more targeted effort to root out terrorists in the east.

Obama met with his war council on Tuesday for nearly two hours to review the draft findings of the report. He ordered changes, but not major ones, Gibbs said. The White House has sought to temper expectations for the report, promising no policy overhauls and no major address to the nation by Obama.

The release of the review comes as the administration copes with the death of Richard Holbrooke, Obama's special envoy to Afghanistan and Pakistan and a central player in the shaping of the strategy.

Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, acknowledged Tuesday in Islamabad that militant havens in Pakistan continue to be a crucial issue.

Returning home from Afghanistan late last week, Defense Secretary Robert Gates said his visits to troops along the mountainous Pakistan border and in the valleys to the south made it clear that U.S.-led NATO forces are fighting two separate wars.

"The strategy in one part of the country will be different than that strategy in another part," Gates told reporters.

In the south, troops are pushing the Taliban out of populated areas, struggling to win the trust of suspicious villagers and trying to build up Afghan forces. In the east, there is a broader effort to stop the Taliban and foreign fighters pouring across the border from Pakistan, including members of the Al Qaeda-linked Haqqani network.

Battling these militants, Gates said, requires targeted attacks, similar to those used in counterterrorism operations, as well as a traditional counterinsurgency campaign that melds firepower with political and economic development.

"In the east, what we're engaged in is a disruption activity and a blocking activity to stop the Taliban who are coming across the border from making it to Jalalabad and to Kabul," he said.

Gates would not call NATO's eastern campaign a pure counterterrorism fight, saying that usually involves targeting specific insurgents or small terror cells. Instead, he said, the battle along the Pakistan border is a broader effort to stop the foreign fighters from entering Afghanistan.

The shift toward a counterterrorism strategy is reflected by the soaring number of bombs being dropped, troops and insurgents being killed and aggressive operations under way along Afghanistan's rugged eastern border with Pakistan.

At Forward Operating Base Joyce near the Pakistan border recently, Lt. Col. J.B. Vowell said that as the fighting surges, the local population is content to keep one foot in the Taliban camp and the other in the NATO and Afghan government's camp, and wait to see who wins.

The battle in the east is heavily dependent on how much Pakistan is willing to do to root out insurgents -- particularly the Haqqani network -- flourishing in havens along the mountainous border.

When asked about frustrations with Pakistan, Gates and military commanders in Afghanistan have tempered their public comments, preferring to focus on the slow steps toward military collaboration among Afghan, Pakistani and U.S. troops.

Maj. Gen. John Campbell, who met with Gates at FOB Joyce, described the often unchecked movement of Haqqani insurgents back and forth across the border. Without more help from Pakistan, Campbell told reporters, progress in eastern Afghanistan will take longer to achieve.

The Associated Press and Reuters contributed to this report.