Even with OPEC forecast to keep its output quota unchanged at a meeting this week, falling oil demand and prospects for increased supply from some member states mean the group’s leader, Saudi Arabia, will have to cut production anyway. The kingdom and its allies Kuwait , Qatar and the United Arab Emirates will need to produce about 2 million barrels a day less in 2014 to prevent a glut, the Centre for Global Energy Studies predicts. That’s equal to annual revenue of about $80 billion at today’s prices. The 12-nation group meets in Vienna on Dec. 4 and will reaffirm its collective limit of 30 million barrels a day, according to 22 of 24 analysts and traders surveyed by Bloomberg News . OPEC is already producing above target, even with output disrupted in member states Iraq , Libya and Iran . Demand for the group’s crude will decline by […]