Pakistan said Tuesday it will boycott an upcoming meeting in Germany on Afghanistan to protest the deadly weekend attack by U.S.-led forces on its troops, widening the fallout from an incident that has sent ties between Washington and Islamabad into a tailspin. The strike Saturday along the Afghan-Pakistani border killed 24 Pakistani troops and triggered fury in Islamabad. Hours after the incident, Islamabad closed its western border to trucks delivering supplies to NATO troops in Afghanistan and said it will review all cooperation with NATO and the United States. The decision to boycott the Bonn conference was taken during a Pakistani Cabinet meeting in the city of Lahore, said three officials who attended the meeting. They spoke on condition of anonymity because they were not authorized to talk to the media ahead of an official announcement. The Dec. 5 meeting was to bring together Western and regional leaders to forge a strategy to stabilize Afghanistan and smooth the planned American withdrawal from the country in 2014. Pakistan is perhaps the most important regional country because of it influence on Afghan Taliban factions on its soil, and U.S. and Pakistani officials had been urging Islamabad to attend. Given the general pessimism about the future of Afghanistan, few had high expectations the conference would result in significant progress. But the absence of Pakistan will make even minor achievements much more difficult. There have been conflicting versions of what led to the attack by NATO aircraft on Saturday, though most accounts say it was likely a case of friendly fire, launched after a joint Afghan and U.S. special forces team received fire from the Pakistan side of the border. NATO and the U.S. are investigating the incident, and have expressed regret at the loss of Pakistani lives. The incident pushed already deeply troubled ties between Pakistan and the United States closer to breakdown after a year that has seen a succession of crises. At the heart of tensions are allegations that Pakistan is supporting militants in Afghanistan in the hope of ensuring a friendly regime there when America withdraws.