European stocks extended last week's retreat on Monday after late losses on Wall Street and as tensions in Ukraine flared again, Reuters reported. By 0705 GMT, the FTSEurofirst 300 index of top European shares was down 0.4 percent at 1,308.17 points, having fallen 3 percent last week. Ukraine gave pro-Russian separatists a Monday morning deadline to disarm or face a "full-scale anti-terrorist operation" by its armed forces, while the UN's Security Council held an emergency session on Sunday night to discuss the crisis.