Commercial tanker traffic resumed through the Strait of Hormuz as OPEC Secretary General Haitham Al Ghais publicly dismissed the International Energy Agency's latest supply glut forecast, labelling the outlook "critical" in remarks carried by CNBC.

The Vienna-based cartel's top official rejected the IEA's surplus projection, arguing that the Paris-based agency has underestimated ongoing underinvestment in long-cycle upstream capacity. The exchange marks one of Al Ghais's more pointed recent interventions in a recurring dispute over non-OPEC supply growth, the speed of the global energy transition, and the appropriate role of hydrocarbon investment through the coming decade.

What does the IEA's outlook assume?

The IEA's monthly Oil Market Report has tracked an accelerating wave of non-OPEC supply from US shale, Guyana, Brazil and Argentina. The agency's central case has pointed to a potential surplus in the second half of the forecast horizon if OPEC+ holds output flat.

OPEC has consistently pushed back, arguing that premature capital flight from long-cycle projects will tighten the balance once demand growth reasserts itself. Al Ghais's choice of "critical" reads as a direct challenge to the agency's methodology, and to its use of non-OPEC supply guidance as the anchor for global balances.

The two institutions have sparred on similar terrain before:

• The IEA has steadily raised non-OPEC supply guidance across successive reports.
• OPEC's secretariat has countered that the agency understates mature-field decline rates.
• Both sides disagree on the lead times required to bring new conventional capacity online.
• The IEA has accelerated its scenarios for electric-vehicle penetration and demand erosion.

Al Ghais's intervention signals that OPEC will continue to anchor its messaging on the gap between announced capacity additions and the volumes needed to offset base decline.

Why does the Hormuz reopening matter for the barrel?

The Strait of Hormuz serves as the only maritime outlet for Gulf producers including Saudi Arabia, Iraq, Kuwait, the UAE and Qatar. Its return to commercial traffic directly affects a meaningful share of seaborne crude and condensate flows, alongside the LNG corridor that feeds Asian and European buyers.

Any sustained closure typically forces tanker operators to reroute around the Cape of Good Hope, prompts emergency stockpile releases by importing agencies such as Japan's METI and South Korea's KNOC, and lifts VLCC freight and insurance costs sharply across the dirty tanker corridor.

For Gulf operators, even a brief transit halt tightens prompt-loading availability for term-contract buyers in India, China and Japan, and supports spot premiums on Middle Eastern grades including Dubai and Murban.

With Gulf export infrastructure running again, market focus shifts to the OPEC+ policy calendar, the IEA's next monthly print, and the durability of Hormuz transit volumes as VLCC fixtures re-establish.

For Asian refiners processing discounted Middle Eastern crude, the combination of resumed flows and a contested supply outlook sets up a familiar playbook: term-contract discipline from Gulf sellers, opportunistic spot buying from Indian and Korean buyers, and continued pressure on the IEA's narrative as OPEC prepares its next communications cycle.

Watch item — the next OPEC+ ministerial meeting, the IEA's forthcoming Oil Market Report, and Strait of Hormuz transit volumes as VLCC fixtures from the Gulf re-establish; margin impact on Asian refiners processing discounted Middle Eastern crude.