NEW YORK - In a policy shift stemming in part from increasing deaths of Pakistani civilians, the Central Intelligence Agency (CIA) has tightened the rules on drone strikes in Pakistan, especially after US military and diplomatic officials complained of damage to the 'fragile Islamabad-Washington relationship, The Wall Street Journal reported on Friday. The newspaper said CIAs 'series of secret concessions include granting the State Department more authority in strike decisions, providing Pakistani leaders with advance notice about more operations, and suspending operations when Pakistani officials visit the US. The changes in the pattern of drone strikes which have killed hundreds of militants, including top commanders were undertaken after a high-level review which strongly backed the drone programme, but raised the bar on operations to minimise diplomatic blowback. 'The bar has been raised. Inside CIA, there is recognition you need to be sure its worth it, a senior official said, adding, that the review had ultimately affirmed support for the CIA programme. The Journal said that there was a measure of discord among administration officials on the interpretations of the outcome of the White House review. 'While some said that the CIA would weigh diplomacy more heavily in its activities, other said the impact was minimum and would remain as aggressive as ever, the paper added. The US drone strikes in Pakistan are currently at their peak with the programme including 14 drone 'orbits. Each 'orbit usually includes three drones, sufficient to provide constant surveillance over Tribal Areas of Pakistan. The CIAs fleet of drones includes Predators and larger Reapers. The drones carry Hellfire missiles and sometimes bigger bombs, can soar to altitude of 50,000 feet and reach cruise speed of upto 230 miles per hour. The American drones over the past decades have become a key element of US national security policy. The drone campaign has killed more than 1,500 suspected militants on Pakistani soil since President Barack Obama took office in 2009, US officials said. The debate in Washington was fuelled by a deadly drone strike on March 17th when missiles from the UAV killed more than 40 people, with infuriated Pakistani leaders claiming that most of them were civilians. The March 17th attack was a 'signature attack, one of the two types used by the CIA which target groups of men believed to be militants or their sympathisers. The bulk of CIA strikes are signature strikes. The second kind of drone strikes are called 'personality strikes which target known terrorist leaders. US officials say that under new rules of engagement, there may be screening of signature attacks but no changes in strikes targeting big terror commanders. The officials also said that there will be no let up in intensified strikes in Pakistan focusing on the militant Haqqani network, although an earlier report in The Washington Post said that the attacks would be eased to open direct talks with the groups representatives.