Since the outbreak of the conflict between the United States and Iran six months ago, the global oil market has undergone significant disruption, challenging the long-standing influence of the Organisation of the Petroleum Exporting Countries and its allies, collectively known as Opec+. Established in 1960, Opec has historically played a central role in managing oil production and prices by coordinating output among its members. However, the ongoing war and its effects on supply routes and infrastructure have weakened Opec+’s ability to control market dynamics.

The conflict has severely impacted one of the world’s most critical oil transit points, the Strait of Hormuz, through which a substantial portion of Opec+ member countries’ crude exports pass. The closure or blockade of this vital corridor has curtailed the physical ability of producers to adjust supplies, rendering Opec+’s announcements of output increases largely symbolic. Despite six declared increments in production since March, tangible effects on supply have been minimal, aside from a brief period of price relief in July during a temporary ceasefire.

Opec+—which includes Opec members alongside allies such as Russia—accounted for approximately 40% of global oil production in July, down from more than 48% prior to the February escalation of hostilities. The decrease reflects both geopolitical disruptions and declining export volumes directly related to the conflict.

Compounding the shifts in supply factors, China has emerged as a pivotal influence on the global oil market in 2026, in part through a notable reduction in its crude imports. Since the war began, China’s oil purchases have fallen by nearly 400 million barrels compared to the same period last year. This decline is attributed to several factors, including government restrictions on fuel exports, lower refining activity, and increased adoption of electric vehicles that reduce oil demand.

China’s changing import patterns have had a substantial stabilizing effect on prices amid what analysts describe as the worst supply disruptions in recent decades. Previously, China’s robust buying had supported rising oil prices globally, but the current moderation in demand is helping to impose a price ceiling despite constrained supply.

The situation is further complicated by the sharp drop in Iranian oil shipped to China, Iran’s largest customer. Iranian exports to China fell from 823,000 barrels per day in July to a provisional 534,000 barrels per day in August, influenced by renewed U.S. pressure and the conflict’s ongoing instability.

Market observers note that what was initially viewed as a temporary shock to Middle Eastern energy supplies is increasingly seen as a structural transformation of global oil trade. The protracted closure of the Strait of Hormuz and sustained market volatility suggest that the disruptions may persist, diminishing Opec+’s traditional role and elevating new actors like China in shaping oil price trajectories. With diplomatic solutions showing little progress, the energy landscape appears poised for a prolonged period of adjustment.