Brent crude futures jumped close to $3 on Friday to their highest since September after a U.S. air strike killed key Iranian and Iraqi military personnel, raising concerns that escalating Middle East tensions may disrupt oil supplies.An air strike at the Baghdad International Airport early on Friday killed Iranian Major-General Qassem Soleimani, head of the elite Quds Force, and Iraqi militia commander Abu Mahdi al-Muhandis, an Iraqi militia spokesman told Reuters.Oil prices were also lifted by China’s central bank saying on Wednesday it was cutting the amount of cash that banks must hold in reserve, releasing around 800 billion yuan ($115 billion) in funds to shore up the slowing Chinese economy. This came shortly after data showed China’s production continued to grow at a solid pace and business confidence shot up.