NEW YORK - Senior US officials are pushing to expand CIA drone strikes beyond Pakistan's tribal areas and into Quetta to pressurize Pakistani leaders to pursue Taliban leaders reportedly based there, The Los Angeles Times reported Monday. But a report in NEWSWEEK said that President Barack Obama was resisting pressures to do so, as such a course would increase civilian casualties and jeopardize US-Pakistan cooperation. "One person standing in the way of expanded missile strikes: President Obama," Mark Hosenball, NEWSWEEK's investigative correspondent wrote in the latest issue of the weekly. Citing five administration officials, the magazine correspondent said the president has sided with political and diplomatic advisers who argue that widening the scope of the drone attacks would be risky and unwise. Meanwhile, Pakistani officials, according to The Los Angeles Times, have warned against any expansion of drone strikes, saying the fallout would be severe. In its front-page story, The LA Times said the proposal for expanding the scope of the CIA-operated drone attacks has opened a contentious new front in the clandestine war, with some administration officials wondering whether unmanned aircraft strikes in a city of 850,000 was a realistic option. Proponents, including some military leaders, argue that attacking the Taliban in Quetta - or at least threatening to do so - is critical to the success of the revised war strategy President Obama unveiled last week. "If we don't do this, at least have a real discussion of it, Pakistan might not think we are serious," the Times cited an unnamed senior US official involved in war planning as saying. "What the Pakistanis have to do is tell the Taliban that there is too much pressure from the US; we can't allow you to have sanctuary inside Pakistan anymore." But others, including high-ranking US intelligence officials, have been more sceptical of employing drone attacks in a place that Pakistanis see as part of their country's core. Pakistani officials have warned that the fallout would be severe. "We are not a banana republic," a senior Pakistani official involved in discussions of security issues with the Obama administration, was quoted as saying. "If the United States follows through, the official said, "this might be the end of the road." The Times said the drone operations "have been conducted with the consent of the government of President Asif Ali Zardari, who has proved a reliable ally to America in his first 15 months in office". "Zardari, however, is facing mounting political woes, and the CIA airstrikes are highly unpopular among the Pakistani public, because of concerns over national sovereignty and civilian casualties," The LA Times said. "If drone attacks now confined to small villages were to be mounted in a sizable city, the death rate of innocent bystanders would probably increase," the newspaper said.. "Obama has endorsed an expansion of CIA operations in the country, approving the deployment of more spies and resources in a clandestine counterpart to the 30,000 additional U.S. troops being sent into Afghanistan. "But the push to expand drone strikes underscores the limits of the Obama offensive. The administration has given itself 18 months to show evidence of a turnaround in Afghanistan. But progress in Pakistan depends almost entirely on drone strikes and prodding a sometimes reluctant ally, which provides much of the intelligence to conduct the strikes, to do more." American and Pakistani officials stressed that the United States has stopped short of issuing an ultimatum to Pakistan. "It just doesn't make a whole lot of sense to use heavy-handed tactics when you've got this kind of relationship," a U.S. counter-terrorism official, was quoted as saying. The senior Pakistani official bridled at the suggestion that Pakistan has been reluctant to target militants in Quetta, saying U.S. assertions about the city's role as a sanctuary have been exaggerated. "We keep hearing that there is a shadow government in Quetta, but we have never been given actionable intelligence," the Pakistani official was quoted as saying. Pakistan is prepared to pursue Taliban leaders, including Omar, even when the intelligence is imprecise, the official said. "Even if a compound 1 kilometer by 1 kilometer is identified, we will go find him." But, he added, "for the past two years we haven't heard anything more." Pakistan is not expected to hand over Mullah Mohammed Omar, the Taliban leader and longtime ally of Osama bin Laden who fled Afghanistan when US forces invaded after the Sep 11, 2001 attacks, The LA Times said. Omar is believed to have used Quetta as a base from which to orchestrate insurgent attacks in Afghanistan, it claimed. But US officials cited by the Times said they have presented Pakistan with a list of Taliban lieutenants and argued that, with a US pullout scheduled to begin in 18 months, the urgency of dismantling the so-called Quetta shura is greater than at any time in the eight-year-old war. The NEWSWEEK report also said that targeting Quetta would also "draw protests from Pakistani politicians and military leaders, who have been largely quiet about the drone attacks as long as they've been confined to the country's out-of-sight border region. "The White House has been encouraged by Pakistan's own recent military efforts to root out militants along the Afghan border, and it does not want to jeopardize that cooperation". Citing unnamed officials, the report said that the administration, which has been reviewing the drone programme for a long time, is likely to continue to debate. It said the administration would even "plan for the possibility of expanding, drone operations in the futureif only to keep the pressure on Pakistan to maintain its current efforts to capture and kill terrorists". A White House spokesperson had no comment on the report.