The United States on Thursday praised Pakistan 's "huge"effort against militancy, with a top Pentagon leader saying that it is up to the South Asian country's to decide the timing for military offensive against militant hideouts in North Waziristan . The Pentagon chiefs - Defense Secretary Robert Gates and chairman Joint Chiefs Staff Admiral Mullen - acknowledged Pakistan 's massive actions to root out militants from its tribal regions bordering Afghanistan. "I think, seven divisions and 140,000 troops in that area. So it is -- it is a huge effort that Pakistan is -- is making," Gates told a press briefing. His comments follow visit by US National Security Advisor James Jones and CIA Director Leon Paenotta to Islamabad this week. Mullen, appearing jointly with the Secretary, said Pakistani army indicated a year ago that there are plans to execute that mission in North Waziristan as part of the overall anti-militancy effort. In view of the already underway efforts, he noted, it makes sense that Pakistan army decides the schedule of the action in North Waziristan . "But very specifically, you know, the timelines are really up to him (Pakistan army chief Gen Kayani)," he said in response to a question. Asked to comment as to what Washington expects from Pakistan in the light of US National Security Advisor and CIA Chief's joint visit to the country this week, Gates noted close US-Pakistani cooperation in the wake of Times Square failed bombing attempt and felt the talks focused on intensifying the existing cooperation. "What we have seen here is yet another new phenomenon, and that is the Tehreek-e-Taliban Pakistan not only trying to overthrow the government of Islamabad, in Islamabad, but also launch attacks against -- outside of Pakistan and, in this case, against us, " the Secretary of Defense replied. "We now have a mutual interest in trying to stop this group, stop it from carrying out attacks inside Pakistan , stop it from carrying out attacks outside of Pakistan , and especially in the United States," he remarked. "And so I suspect that the main theme of these talks was -- that were held was, how can we intensify our cooperation in dealing with this mutual threat that we face? My impression has been that there has been close cooperation since the (Times Square) bomber (a Pakistani-American) was arrested. So I think it's more about that than any qualitative change," Gates added. In his remarks, Mullen expressed understanding of Pakistani point of view that its military is currently stretched. "Well, as far as this visit that General Jones and Director Panetta took, I think I really need to refer you to them. And the fact is, I haven't -- I actually haven't spoken with either of them since they -- since they returned," he responded to a question. "I understand and believe, that, you know, he's stretched. He (Gen Kayani)'s got two fronts. He's got a military that's lost a lot of soldiers, sacrificed a great deal. And so that -- it makes a lot of sense to me, you know, that he does get to pick this timeline," Mullen stated. "They're struggling in the build phase in Swat, behind the security that he's established there. So this is not a one-of kind of thing. It's really part of an overall campaign plan." the admiral added Mullen said the Pakistani army chief has always lived up to his word.