The report, which has not been officially released, focuses on U.S. State Department efforts to keep the bomb-making material from Pakistan from going to Taliban insurgents in Afghanistan, USA Today reported.
The GAO report quotes U.S. officials accusing the Pakistani government of delaying visas for American officers fighting improvised explosive devices in Pakistan.
"U.S. agencies have encountered ongoing challenges to their efforts to assist Pakistan, such as delays in obtaining visas and in the delivery of equipment," the report said.
The report said the State Department must do a better job monitoring progress of U.S. efforts to fight IEDs in Pakistan and the State Department agreed.
IEDs are the leading killer of U.S. troops in Afghanistan, the Pentagon's Joint IED Defeat Organization said. It estimated 83 percent of IEDs used in attacks on U.S. troops are made with fertilizers produced in Pakistan. In the 12 months ending April 30, there were 16,165 IED incidents, a 2 percent increase from the same period a year earlier.
Relations between the United States and Pakistan have been strained, and U.S. officials have said Pakistan has provided havens for insurgents. Pakistan blocked shipments of supplies to NATO troops after U.S. forces accidentally killed 24 Pakistan soldiers in November and has not reopened supply routes.