The Pakistani government has called on the US Embassy in the capital Islamabad to phase out over 250 American officials in the country within the next 30 to 40 days.
The US officials are reportedly assigned various duties such as logistic support and audit and accounts monitoring. Most of them are said to be involved in high-level espionage and anti-state activities, Pakistan's The Nation newspaper reported on Wednesday.
The report added that US Ambassador to Pakistan Cameron Munter is coming back to Pakistan after cutting short his vacation to deal with the situation.
Tensions between Islamabad and Washington increased following a secret US raid into Pakistan in May that killed al-Qaeda leader Osama bin Laden.
Pakistani military has since been under pressure to explain why US military helicopters freely carried out the operation on Pakistani soil.
Pakistan's defense ministry later ordered the United States to leave a remote desert airbase in the southwestern Baluchistan Province.
The US had long been carrying out its unauthorized drone attacks in Pakistan from the Shamsi airbase in Baluchistan.
US-Pakistan relations are already strained over the civilian casualties caused by the non-UN-sanctioned US drone attacks, which Pakistan has repeatedly condemned as violations of its sovereignty.
The aerial attacks, initiated by former US president George W. Bush, have escalated under President Barack Obama's administration.