WASHINGTON: The CIA suspended its long-standing use of an air base in Pakistan as a launch site for armed drones targeting members of al Qaeda and other militant groups three months ago, according to US and Pakistani officials.

In a report published in Washington Post newspaper, Pakistan in recent days has publicly declared that it "ended" all US flights from the base in the wake of the secret US commando raid that killed al Qaeda leader Osama bin Laden in May.

But US and Pakistani officials said the launches were halted in April, weeks before the bin Laden raid, after a dispute over a CIA contractor who fatally shot two Pakistani citizens in Lahore in January.

All U.S. drone strikes in the past three months have been launched from Afghanistan, in the vicinity of Jalalabad, according to the officials, who spoke about intelligence matters only on the condition of anonymity.

The New America Foundation, which tracks the strikes, has listed 23 such raids since the beginning of April, all but one in Pakistan's tribal regions of North and South Waziristan. A June 20 attack was reported in Kurram, an area above North Waziristan along the Afghanistan border.