Iran Strait Crisis: Global Oil Reserves Tapped as Supply Falters

The effective closure of the Strait of Hormuz following escalating conflict with Iran is triggering a global scramble for oil, prompting countries to release strategic reserves at a scale unseen since 2022. The disruption, which began on February 28, 2026, with attacks on oil infrastructure in neighboring countries, has already pushed Brent crude above March 11 to over $100 a barrel, a price not seen since 2022.

The Strait of Hormuz, a narrow waterway between Iran and the Arabian Peninsula, is the world’s most important oil transit choke point. Approximately 20 percent of global oil supplies, largely destined for Asian markets, pass through the strait. Iran’s actions, initially framed as adjustments to insurance contracts for tankers, have escalated to threats of attacks on shipping, effectively halting passage. Oil producers in the Gulf region, including Iraq, Kuwait, Saudi Arabia, and the United Arab Emirates, have already begun curtailing production as storage capacity fills, exacerbating the supply crunch.

Strategic Reserves Tapped in Unprecedented Drawdown

In response to the crisis, the 32 member countries of the International Energy Agency (IEA) agreed on March 11, 2026, to release 400 million barrels of oil from their strategic emergency reserves. This is a significantly larger release than the 182 million barrels deployed after Russia’s invasion of Ukraine in 2022, signaling the severity of the current situation. The United States will contribute 172 million barrels to the effort, with 45.2 million barrels already lent to oil companies as of March 9, 2026.

Strategic petroleum reserves (SPR) are government-held stockpiles of crude oil intended to mitigate disruptions to supply. These reserves, often purchased through agreements with private companies, are designed to provide a buffer during emergencies like wars or economic crises. The IEA collectively holds over 1.2 billion barrels of public emergency oil stocks, supplemented by 600 million barrels held by private organizations under government mandate.

Global Stockpiles and National Responses

While the US and IEA nations are coordinating a response, several countries are taking independent action. China, which is not an IEA member, holds the world’s largest strategic oil reserve, estimated at around 1.13 billion barrels as of 2025. Despite not officially publishing inventory figures, China’s state-owned refiners, like Sinopec, are reportedly seeking permission to utilize reserves as the conflict in Iran intensifies and threatens supply. Sinopec President Zhao Dong indicated the company anticipates government policies to support refinery production.

Japan, another major oil importer, announced on March 16, 2026, it would release 80 million barrels from its reserves, enough to cover 254 days of domestic consumption. Japan established its national oil reserve system in 1978 following the oil crises of the 1970s, recognizing its vulnerability to disruptions in foreign oil supplies. The UK, holding approximately 38 million barrels of crude and 30 million barrels of refined products, is contributing 13.5 million barrels to the IEA release.

European Union member states, including Germany, France, Spain, and Italy, are also drawing down their strategic reserves. Germany holds 110 million barrels of crude and 67 million barrels of finished petroleum products, while France has around 120 million barrels. Spain approved the release of 11.5 million barrels over 90 days, and Italy is releasing reserves representing 90 days of net oil imports.

A Shifting Landscape and Uncertain Future

The Trump administration’s attempts to de-escalate the situation, including calls for a naval escort and a 48-hour ultimatum to Iran, have so far proven unsuccessful. A temporary waiver allowing the delivery of sanctioned Russian crude, intended to alleviate price pressures, has had a limited impact, with Brent crude remaining near $100 a barrel as of March 13, 2026. The administration’s subsequent pause on strikes against Iranian power plants and claims of ongoing talks with Iran have been denied by Tehran, adding to the uncertainty.

The situation remains highly volatile. The effectiveness of the strategic reserve releases in stabilizing the market will depend on the duration of the disruption to oil flows through the Strait of Hormuz and the willingness of Iran to continue its current course. Observers should monitor further developments in the military conflict, any potential diplomatic breakthroughs, and the response of major oil-consuming nations to the evolving crisis. The potential for further escalation, including attacks on energy infrastructure in the region, remains a significant concern.