The oil supply shock caused by the Iran war has eroded global demand for crude — but a lasting resolution to the conflict could drive a surge in supply volumes and trigger a major oil overhang next year, the International Energy Agency said on Wednesday. In its latest monthly oil market report, the IEA slashed its 2026 demand outlook to 1.1 million barrels a day year-over-year in 2026. That's a 700,000-barrel-per-day downgrade from last month's estimate, after deliveries plunged by 5 million