Iran closes Strait of Hormuz; hundreds of oil tankers stranded as OPEC+ announces modest output increase

On Saturday night, Iran's Revolutionary Guard issued a stark directive: no vessel would be permitted passage through the Strait of Hormuz. By Sunday morning, the consequences were visible on every shipping tracker. Hundreds of oil tankers sat idle in the waters off Iraq, Saudi Arabia, and Qatar—some anchored in open sea, others clustered near the coasts of the United Arab Emirates and Oman, waiting for a passage that would not come. The Iranian government had closed the world's most critical petroleum chokepoint, the waterway through which one-fifth of all global oil flows, and the market had not yet opened to price the shock.

Ship-tracking data compiled by Reuters painted a picture of paralysis. The tankers were not scattered randomly but concentrated in the Gulf's major production zones, their crews receiving repeated radio warnings from Iranian military forces. At least a hundred vessels were stranded outside the strait itself, unable to approach. The blockade had begun abruptly, following military escalations between the United States, Israel, and Iran, and it had frozen the flow of crude, liquefied natural gas, and other petroleum products in a matter of hours.

Analysts braced for Monday's market opening, expecting oil prices to surge. Brent crude had already climbed to seventy-three dollars per barrel on Friday—the highest level since July—on mere speculation of conflict. Now the speculation had become fact. Some veteran observers, including Helima Croft of RBC Capital Markets, warned that Middle Eastern leaders had privately cautioned Washington that a full war with Iran could push prices past one hundred dollars. Barclays analysts echoed the forecast. The question was no longer whether prices would rise, but how far.

Yet the blockade contained a paradox that analysts were quick to identify. Iran's own economy depended almost entirely on the strait it had just closed. Roughly ninety percent of the country's oil exports flowed through a single terminal in the Persian Gulf, meaning every barrel destined for international markets had to pass through the very waterway now sealed by Iranian decree. João Victor Marques, an energy researcher at FGV in Brazil, explained the bind plainly: Iran was already strangled by Western sanctions and wracked by internal economic crisis, its currency in free fall. The regime needed dollars to survive. Blocking the strait for any extended period would amount to self-asphyxiation.

On Sunday, OPEC+ convened an emergency session. Only eight members attended—Saudi Arabia, Russia, the United Arab Emirates, Kazakhstan, Kuwait, Iraq, Algeria, and Oman—a smaller coalition than the full cartel. They debated production increases ranging from 137,000 barrels per day to 548,000. What they settled on was far more modest: 206,000 barrels daily, a figure representing less than two-tenths of one percent of global supply. The decision reflected a hard reality. Outside of Saudi Arabia and the UAE, OPEC+ had almost no spare capacity to deploy. The cartel had a history of opening the taps during supply shocks, but this time, the tools available were blunt and limited.

Saudi Arabia had been quietly ramping up production and exports in recent weeks, sources told Reuters, apparently in anticipation of the American strikes on Iran. The kingdom and the Emirates would now bear the burden of trying to offset the lost Gulf shipments, yet even they faced a problem: their own exports could not leave the region until the strait reopened. The blockade had created a trap. OPEC+ could announce increases, but those barrels could not reach the market. The modest production bump was less a solution than an acknowledgment of helplessness.

When markets reopened Monday, the world would learn what the stranded tankers already knew: the global oil system had fractured at its most vulnerable point. Prices would move sharply upward. Shipping insurance would spike. Refineries would begin calculating how long they could operate on existing inventories. And Iran, having seized a weapon of economic leverage, would discover that the weapon was pointed as much at itself as at its adversaries. The strait remained closed, the tankers remained still, and the clock was running on how long any of the parties involved could afford to let it.