By Pentagon Correspondent Barbara Starr

The Central Intelligence Agency and the U.S. military have stepped up unilateral strikes against the Haqqani network over the past year, a senior U.S. official has confirmed to CNN.

The news follows public comments by top U.S. officials this week voicing frustration with Pakistan's lack of action against the terror network.

The senior official said the CIA and the U.S. military agreed last year to increase targeting of the Haqqani terrorist network inside Pakistan after Haqqani-backed insurgents stepped up their attacks across the border inside Afghanistan against U.S. troops and Afghan targets.

The Pentagon asked the CIA to step in last year and as a result, at one point in 2010, 20% of armed CIA drone attacks in Pakistan were aimed at Haqqani targets, the official said.

"A deliberate decision was made to start ramping up targeting the Haqqanis in 2010," he said. CIA drone attacks are specifically aimed at al Qaeda and their "militant allies," which has long allowed for groups like the Haqqanis and the Pakistani Taliban to be targeted.

The official declined to be identified because of the sensitive nature of the information. He pointed out that the drone operations amount to unilateral U.S. action against the Haqqanis inside Pakistan, even as U.S. military forces have increasingly targeted Haqqanis inside Afghanistan.

But how successful either operations have been remains a question in light of the Haqqanis' continuing ability to stage high-profile attacks. FULL POST