WASHINGTON - The new CIA director, Leon Panetta, has said the spy agency's campaign against militants in tribal areas of Pakistan was the 'most effective weapon' the Obama administration had to combat al-Qaeda's top leadership. The CIA in recent months has intensified its covert campaign of drone attacks in the tribal areas, carrying out more than 30 strikes against Qaeda and Taliban leaders from drone aircraft. Panetta stopped short of directly acknowledging the missile strikes, but he said that 'operational efforts' focusing on Qaeda leaders had been successful, according to his remarks published in The New York Times on Thursday. "It is for that reason that the president and the vice president and everyone else supports continuing that effort," he said. Panetta's comments were seen as the most candid to date about the Obama administration's decision to continue - and in some cases expand on - the Bush administration's covert operations against Al-Qaeda. Privately, the US officials have claimed that the missile strikes have killed a large cadre of Qaeda leaders since last summer, although Pakistani intelligence officials say they fear the drones are further destabilising their already fragile country. Panetta's comments came during a discussion with reporters on Wednesday, two weeks after he took over at CIA headquarters. He also said the spy agency had begun producing a daily report to the White House about the world financial crisis - another sign that American intelligence agencies are increasingly nervous about how it could affect global security. The Pakistani concerns about the drone strikes came up during meetings this week in Washington between Obama administration, Pakistan military and civilian leaders. Despite hours of discussions on Tuesday and Wednesday, the US and Pakistani officials remained somewhat wary of each other's motives and strategies to fight militants, the Times said. Pakistani officials have told their American counterparts that they are doing everything they can to fight extremists in the mountainous border region. The delegation also sought to reassure administration officials that their recent deal to allow Islamic law in Swat Valley was not surrendering to the Taliban. "I guess I remain sceptical," Panetta said.