in bringing the United States to the negotiations table with the Afghan Taliban and the Haqqani Network, had already halted those efforts according to an unnamed Pakistani official close to the military establishment. While addressing a Senate committee, the Minister of Foreign Affairs Hina Rabbani Khar warned that a repeat incident could end Pakistan's support to the United States in its war against militancy. "Enough is enough. The government will not tolerate any incident of spilling even a single drop of any civilian or soldier's blood. Pakistan's role in the War on Terror must not be overlooked." She added that "the sacrifices rendered by Pakistan in the war on terror are more than any other country. But that does not mean we will compromise on our sovereignty." Pakistan's refusal to attend Bonn Conference In the wake of the NATO attacks, the Pakistani government refused to attend the Bonn conference scheduled on 5 December 2011. The event in Bonn, Germany is an important international conference on Afghanistan. International pressure over Pakistan mounted as it refused to attend the Bonn conference. Secretary Hillary Clinton contacted the Pakistani Prime Minister but her plea was rejected because Pakistani public opinion prohibited attendance. The conference was generally regarded as a disappointment, partially because of Pakistan's absence. Revision of western-border rules of engagement Pakistan also strengthened its air defences and surveillance along the Afghanistan border as a precaution against any future incursions. DGMO Major General Ashaq Nadeem was quoted saying "We can expect more attacks from our supposed allies". Pakistan's army chief General Ashfaq Parvez Kayani issued directions to commanders posted at the border to fire without permission if any further aggression is received. According to a Pakistani security official, Pakistan had upgraded to a "fully equipped air defence system" on the Afghan border which has the capability of detecting, tracing and shooting down any aircraft. These weapons notably include indigenous shoulder-to-air Anza Mk-III missiles and anti-aircraft guns. The Pakistan Air Force cancelled leave for all its air reconnaissance-related personnel and deployed aircraft to start a round-the-clock combat air patrol over the Afghan border to prevent all intrusions including drone attacks. Reactions The already fractured relationship between Pakistan and the United States fell to a new low following the incident, with the Pakistani government and military establishment reassessing their diplomatic, political, military and intelligence relationship with the United States. Government and military The Foreign Ministry of