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 ClintonThe politics of the rising American electorate Sanders: Halting TPP, pipeline are 'lessons' in how to fight Trump Madonna on Trump win: 'Women hate women' MORE and Secretary of Defense Robert Gates. "This is particularly concerning as the Congress again considers increasing security assistance to Pakistan."

The letter was signed by Sens. Max BaucusMax BaucusThe mysterious sealed opioid report fuels speculation Lobbying World Even Steven: How would a 50-50 Senate operate? MORE (D-Mont.), Dianne FeinsteinDianne FeinsteinThis Week in Cybersecurity: Dems press for information on Russian hacks Overnight Defense: Armed Services chairman's hopes for Trump | Senators seek to change Saudi 9/11 bill | Palin reportedly considered for VA chief Lawmakers praise defense bill's National Guard bonus fix MORE (D-Calif.), Robert MenendezRobert MenendezThe right person for State Department is Rudy Giuliani Warren, Menendez question shakeup at Wells Fargo Democrats press Wells Fargo CEO for more answers on scandal MORE (D-N.J.), Ben Nelson (D-Neb.) and Jon TesterJon TesterRed-state Dems face tough votes on Trump picks Montana Republican warns of Senate challenge to Tester Vulnerable Dems ready to work with Trump MORE (D-Mont.).

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.