The source, who says he runs a network of spotters primarily in North and South Waziristan, described for the first time how U.S.-Pakistani cooperation on strikes works, with his Pakistani agents keeping close tabs on suspected militants and building a pattern of their movements and associations.

“We run a network of human intelligence sources,” he said. “Separately, we monitor their cell and satellite phones.

“Thirdly, we run joint monitoring operations with our U.S. and UK friends,” he added, noting that cooperation with British intelligence was also extensive.

Pakistani and U.S. intelligence officers, using their own sources, hash out a joint “priority of targets lists” in regular face-to-face meetings, he said.

“Al Qaeda is our top priority,” he said.