The United Arab Emirates will leave OPEC effective Friday, stripping the oil cartel of its third-largest producer and further weakening its leverage over global oil supplies and prices. The UAE in recent years has pushed back against OPEC production quotas it felt were too low. Regional politics are also likely a factor in the decision announced Tuesday. The UAE has had increasingly frosty relations with Saudi Arabia, OPEC’s largest producer, over political and economic matters in the Mideast, even after both were attacked by fellow OPEC member Iran during the war. The UAE’s withdrawal from OPEC won’t necessarily have any immediate effects in markets because supplies are being constrained by the war in Iran.