"Nothing has changed our efforts to go after terrorists, and nothing will change those efforts," Panetta was quoted as saying by 'The Washington Post'.

The drone attack, against which there has been public backlash inside Pakistan, has been highly successful, the CIA chief said.

"It is for that reason that the President (Barack Obama) and the Vice President (Joe Biden) and everyone else supports continuing that effort," he was quoted as saying by 'The New York Times'.

Panetta however, refrained from giving any details about the drone attacks.

"I don't think we can stop just at the effort to try to disrupt them. I think it has to be a continuing effort, because they aren't going to stop," Panetta was quoted as saying by 'The Washington Post'.

Meanwhile, in a series of interviews, the visiting Pakistani Foreign Minister Shah Mahmood Qureshi opposed the drone attacks and said he would take up this during his meetings with American leaders.

The drone strikes and raids are proving effective, having killed as many as 80 al-Qaeda fighters in the past year, the 'New York Times' quoted unidentified Pakistani intelligence officials as saying.