Five Democratic senators on Tuesday called on the Obama administration to assess Pakistan's cooperation with the U.S. in fighting terrorism. 

They said Congress would use this assessment to decide whether to continue granting foreign aid to Pakistan.

"The discovery of Osama bin Laden in a military town less than forty miles from the Pakistani capital of Islamabad indicates, at a minimum, a lack of commitment by the Pakistani military to aggressive cooperation with the United States," the senators wrote in a letter to Secretary of State Hillary ClintonHillary Rodham ClintonRNC paid little-known firm for reports on Clinton: report Dem rep: 'We must pause the entire Trump agenda' until Russia investigation complete New England Patriots to visit White House on April 19 MORE and Secretary of Defense Robert Gates. "This is particularly concerning as the Congress again considers increasing security assistance to Pakistan."

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The senators wrote that Pakistan is the third-largest recipient of U.S. aid, after Afghanistan and Israel, receiving $2.7 billion in 2010.

"[I]t is incongruous to be providing enormous sums to the Pakistani military unless we are certain that it is meeting its commitment to locate, disrupt and dismantle terrorist threats inside its borders," they wrote.

They asked specifically for an assessment of Pakistan's commitment to end support to extremist groups, preventing them from operating in Pakistan, and strengthening its counterterrorism and anti-money laundering laws.

"We believe that conducting this assessment will be crucial for the Congress to determine whether to provide the full range of security assistance called for in the FY 11 Continuing Resolution and the FY 12 budget," they said.