Islamabad officials decided to boycott the Bonn Conference on Afghanistan next month in protest against the cross-border NATO air strike that killed at least 24 of its soldiers.The boycott on the crucial conference to be held on December 5 to discuss ways to end the conflict in Afghanistan was made during an emergency meeting of the Defense Committee of the Pakistani Cabinet chaired by Premier Yousuf Raza Gilani. Foreign Ministers of over 90 countries are likely to attend the Bonn Conference that is expected to discuss key issues like the withdrawal of foreign forces from Afghanistan and negotiations with the Taliban. US Secretary of State Hillary Clinton had planned to meet Pakistani Foreign Minister Hina Rabbani Khar on the sidelines of the conference. \"Pakistan\'s absence from the conference would be a major setback to the US-led efforts for bringing the Taliban to the dialogue table,\" the Pakistani media said in reports released on Sunday. During Saturday\'s meeting, Pakistan\'s Army Chief Gen Ashfaq Parvez Kayani was \"composed but firm about his approach\" while Gilani was in \"utter anxiety and hardly could control his emotions\" over the NATO air strike on an army post in the Mohmand tribal region, a report by the News daily said. Foreign minister Khar was among those who were \"visibly upset about the episode,\" the report said. A statement issued after the meeting said the Pakistan government had decided to close all NATO supply routes. The government also asked the US to vacate the Shamsi airbase, believed to be the main base for CIA-operated drones, in 15 days. The News report said Gilani referred to the resolution on national security adopted at a joint sitting of Parliament following the US raid that killed Osama bin Laden and suggested the government would again take up the matter in Parliament. Gilani is expected to make a decision in a day or two about summoning another joint sitting of Parliament. The meeting of the Defense Committee of the Cabinet also decided to strengthen air defenses on the border with Afghanistan. Air surveillance would be enhanced so that the response to any further incursion would be \"effective\", the report said.