The United Arab Emirates (UAE) said on Tuesday it quit Opec and Opec+, dealing a heavy blow to the oil exporting groups and their de facto leader, Saudi Arabia, at a time when the war on iran has caused a historic energy shock and unsettled the global economy. The stunning loss of the UAE, a longstanding Opec member, could create disarray and weaken the group, which has usually sought to show a united front despite internal disagreements over a range of issues from geopolitics to production q...