OPEC+ has delayed a production-capacity review that will help determine members’ 2027 oil quotas after the US-Israeli war on Iran disrupted Middle East projects and clouded estimates of future output. Ordered in late 2025 and originally due by the end of September 2026, the review is now expected to be completed by mid-November, according to sources close to the matter. DeGolyer and MacNaughton is assessing members other than Russia, Iran and Venezuela, which are under US sanctions, and is due to submit its report in mid-November, allowing OPEC+ to consider the findings at a late-November meeting. The assessment is intended to independently measure each member’s maximum sustainable production capacity, a key metric in quota negotiations. Delayed projects and missing data submissions could affect future allocations, with lower capacity assessments potentially weighing on quotas and expanded capacity supporting requests for higher output. The United Arab Emirates left the alliance in May after seeking a higher quota, while Iraq is also seeking a higher quota and has considered leaving OPEC.