A report by the US State Department says harassment of American diplomats by the Pakistani government has increased dramatically.
The US raid on Osama Bin Laden's compound in May last year and a NATO air strike that killed 24 Pakistani soldiers were identified as turning points.
Pakistan withdrew military co-operation after the air strike in November.
The BBC reports there has been marked deterioration of US-Pakistan relations in recent months. But interference by Pakistani officials reached "new levels of intensity" in 2011.
The report acknowledged that the Pakistani government previously interfered with US officials on its soil.
However, it said the problem had become much worse and recommended that the issue should be taken up by the United States with Pakistan at the highest levels of government.
"The United States is clearly the principal target," the report said.
It described the harassment as "deliberate, wilful and systematic" and said examples of the obstruction included delays in getting visas, holding up shipments for construction projects and aid programmes, and surveillance of employees.
The report was based on visits to US missions in the Pakistani cities of Islamabad, Karachi, Peshawar, and Lahore.
It describes the raid on Bin Laden's compound as a double embarrassment for the Pakistani government, as it was evidence of incompetence and the government's inability ''to detect or defend against a military intervention".
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