The new chief of US and Nato forces in Afghanistan has vowed to protect Afghan civilians when he takes up his post. Gen David Petraeus has been briefing allies and partners at Nato Headquarters in Brussels before heading to Kabul.<br/><br/>Gen Petraeus said although he was reviewing rules of engagement, he was committed to reducing loss of innocent civilian lives to an absolute minimum.Gen Petraeus is replacing Gen Stanley McChrystal, who was forced out after a controversial article in a magazine. He is one of America's best-known military figures and is widely credited with having turned around the military situation in Iraq with a surge there.