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OPEC and Middle East Supply Watch

Organization of the Petroleum Exporting Countries and its allies (OPEC+) quotas, the Middle East supply disruption, Gulf loadings, and Saudi pricing: the state of the world's swing supply.

Read this page as the supply-side bid for sour barrels: OPEC+ quota decisions set the ceiling, the Middle East conflict sets the actual flow, and Saudi official selling prices set the price signal Asian buyers see. Each bullet carries its vintage, so read 2026 wartime data against the pre-war baselines in the Hormuz watch. The disagreements log flags where trackers and officials genuinely diverge.

Middle East supply sets the world price of oil and the value of every sour barrel competing with Western Canadian Select. A prolonged shortfall in medium and heavy sour supply from the Gulf supports heavy crude pricing globally and keeps refinery demand for sour barrels strong. If OPEC+ restores output faster than expected or the war ends, the sour premium collapses and Canadian barrels lose their relative bid.

Updated September 24, 2026 · refreshes every 14 days

The pause: quotas held after the unwind

• OPEC+ approved a 188,000 barrel-per-day production increase for September 2026 and then agreed to hold required production levels flat for October, the first pause since the unwind began in April; required levels include Saudi Arabia at 10.478 million barrels per day, Russia at 9.949 million, Iraq at 4.431 million, Kuwait at 2.676 million, Kazakhstan at 1.628 million, Algeria at 1.007 million, and Oman at 0.841 million, with the next meeting scheduled for October 4.
  2026-09-07 Rigzone
• Reuters sources said on July 28, 2026 that OPEC+ was likely to keep production increases on hold after September, noting that most of the announced hikes existed only on paper because the Iran war forced Middle East export cuts, and that the group was not expected to change policy until year-end, with 2027 quotas to be set after a capacity review.
  2026-07-28 Reuters via Energy News (OE Digital)

The war's mark on Gulf output

• OPEC's July 2026 Monthly Oil Market Report showed June secondary-source output of 22.002 million barrels per day, up 3.051 million month on month, but the composition reflects the war: Saudi Arabia produced 6.847 million barrels per day (down 99,000), Iraq 1.970 million (up 446,000), Kuwait 1.452 million (up 880,000), Iran 2.441 million (up 155,000), and the United Arab Emirates 3.809 million (up 1.642 million).
  2026-07 (June 2026 data) Organization of the Petroleum Exporting Countries (OPEC) Monthly Oil Market Report
• The EIA's September 2026 Short-Term Energy Outlook estimated that 6.7 million barrels per day of Middle East crude production was shut in during August, up from 5.0 million in July, easing to about 5.7 million in the fourth quarter, with regional output staying below pre-conflict averages until the second quarter of 2027.
  2026-09 US Energy Information Administration (EIA) Short-Term Energy Outlook, via Oil and Gas Journal summary
• The EIA estimated that the conflict has removed about 400 million barrels from global oil inventories since the start of the year, and forecast Brent crude near $90 per barrel in the second half of 2026 amid the Middle East disruptions.
  2026-09 US Energy Information Administration (EIA) Short-Term Energy Outlook, via Oil and Gas Journal summary

Gulf loadings: the September snapshot

• Kpler data cited September 23, 2026 showed about 6.5 million barrels per day flowing through the Strait of Hormuz so far in September, the highest since the June ceasefire but down from roughly 20 million barrels per day before the conflict; very large crude carrier (VLCC) freight from the Middle East Gulf to China hit an all-time high of about $30 per barrel, roughly 25 percent of cargo cost.
  2026-09-23 OilPrice.com
• A September 10-11, 2026 drone attack shut Saudi Arabia's East-West (Petroline) pipeline, a 1,200-kilometer line with about 7 million barrels per day of capacity; Kpler estimated storage at Yanbu below 15 million barrels, and Aramco cancelled or delayed some September cargoes to European refiners.
  2026-09-17 TankTerminals
• Three sources told Reuters on September 23, 2026 that Saudi Arabia resumed pumping through the East-West pipeline on September 22 after the drone attacks; Iraq is exporting more than 3 million barrels per day and targeting over 600,000 barrels per day through the Turkey pipeline, while preliminary August estimates of total Iraqi exports differed between trackers: Vortexa at 2.3 million barrels per day and Kpler at 2.17 million, versus pre-war figures of 3.7 million and 3.362 million respectively.
  2026-09-23 Reuters via Roydad Naft
• Kpler data cited September 22, 2026 put Asia's crude imports at 23.96 million barrels per day in September, the highest since February and up from 23.38 million in August, though still 13 percent below pre-conflict levels; US Energy Secretary Chris Wright said on September 21 that as much as 15 million barrels per day was still leaving the Middle East, while tanker-tracking services put observed exports lower.
  2026-09-22 Maritime Professional

Saudi pricing: the sour barrel signal

• Aramco cut its July 2026 Arab Light official selling price (OSP) for Asia by $11 per barrel to $1.50 below the Oman/Dubai benchmark, the largest single-month reduction in more than two decades; traders said Asian buyers, already satisfied with their crude slate, were unlikely to be swayed, with renewed Iranian competition for Asian buyers cited as a factor in the cut.
  2026-07-07 Energy News (OE Digital)

The demand revisions

• OPEC's September 2026 Monthly Oil Market Report cut its 2026 oil demand growth forecast for the fifth straight month, lowering it by 200,000 barrels per day to 380,000, with total consumption at 105.84 million barrels per day; it raised the 2027 growth forecast to 2.36 million barrels per day and noted July OPEC+ output of 38.055 million barrels per day.
  2026-09-15 Argus Media
• The United Arab Emirates withdrew from OPEC and OPEC+ effective May 1, 2026, according to the September report, which also cut cumulative 2026 demand growth by about 1 million barrels per day since the US-Iran war began.
  2026-09-15 Argus Media

Where sources disagree

• Iraqi August 2026 export estimates: Vortexa vs Kpler. Vortexa estimated 2.3 million barrels per day of Iraqi exports in August versus a pre-war 3.7 million; Kpler put it at 2.17 million versus a pre-war 3.362 million, as reported by Reuters. Different tracker methodologies, not a data error.
• Middle East oil outflows in September 2026: US Energy Secretary Chris Wright (public statement, September 21, 2026) vs tanker-tracking services. Wright said as much as 15 million barrels per day was still leaving the Middle East; tanker trackers reported lower observed exports. Claimed versus tracked, unresolved.

For the WCSB book, this page is the fundamental backdrop behind every TMW and ARV print: tight Gulf sour supply is what is keeping the heavy basis bid right now. If Hormuz flows normalize or Saudi pricing turns aggressive again, expect the Canadian differential complex, including TMW and ARV, to soften first at the margin.

Standing watch

What the daily feed updates on this page.

• OPEC+ monthly output decisions and required production levels
• OPEC Monthly Oil Market Report secondary-source output and demand revisions
• US Energy Information Administration (EIA) Short-Term Energy Outlook Middle East shut-in estimates
• Kpler and Vortexa Hormuz and Yanbu loading snapshots
• Aramco official selling prices to Asia
• East-West Pipeline flow status and Yanbu crude loadings

Gaps

• Exact per-country September compliance versus required levels was not yet published at the time of writing.
• Day-to-day Hormuz barrel flows are tracker estimates; the US Energy Information Administration (EIA) quarterly volume series lags by months.
• The 2027 quota framework depends on an OPEC+ capacity review not yet completed.

Sources