SYDNEY — As the effective closure of the Strait of Hormuz drags into its fourth week, Australia’s critically low fuel reserves — just 36 days of petrol, 32 days of diesel and 29 days of jet fuel — are coming under intense pressure, raising fears that a prolonged disruption could force rationing, empty regional bowsers and push unleaded prices toward or beyond $3 a litre.

The narrow waterway between Iran and Oman normally carries about 20 million barrels of oil per day, roughly one-fifth of global seaborne crude and significant LNG volumes. Since late February, when U.S. and Israeli strikes on Iranian targets prompted Tehran to restrict shipping with mines, drones and speedboats, most international tanker traffic has halted. Only limited vessels, often carrying Iranian oil or from “friendly” nations, continue to pass, according to shipping trackers and government statements.

Brent crude traded around $103 per barrel on Tuesday, March 24, 2026, after volatile swings that briefly pushed it above $114. The surge has already translated into sharp rises at Australian pumps. Unleaded 95 jumped 31.8% between late February and mid-March — the fastest increase among developed nations — with national averages climbing above $2.19 a litre and Perth hitting near $2.26. Regional areas have seen even steeper spikes and sporadic shortages amid panic buying.

Australia imports roughly 90% of its refined petroleum products. While only a small direct share of crude comes straight from the Gulf, many key suppliers — Singapore, South Korea, Japan and others — rely heavily on crude routed through Hormuz. Analysts estimate that up to 50% of Australia’s diesel imports are indirectly exposed. With limited domestic refining capacity after years of closures, the country depends on imported petrol, diesel and jet fuel to keep trucks moving, planes flying and farms operating.

Energy Minister Chris Bowen has repeatedly assured the public that supplies remain “steady” and that all expected shipments have arrived as scheduled. Latest government figures show Australia holding about 36 days of petrol, 32-34 days of diesel and 29-32 days of jet fuel at normal consumption rates. These stocks include fuel already on tankers heading to Australian ports. The government has released roughly six days’ worth of petrol and five days’ worth of diesel from the strategic reserve — the first such drawdown since the 2022 Ukraine invasion — to ease pressure on regional areas hit hardest by panic buying.

Even so, experts warn the buffer is razor-thin. Australia is the only International Energy Agency member that consistently fails to meet the 90-day reserve requirement, with holdings often hovering between 50 and 58 days when measured against net imports. The minimum stockholding obligation introduced in 2023 has lifted commercial reserves, but they remain far below levels in countries like Japan or the United States.

A prolonged Hormuz shutdown could quickly exhaust these reserves. Oxford Economics and other analysts have modelled scenarios in which a full closure lasting one month pushes Brent toward $130 a barrel, while a three-month disruption risks far steeper spikes and global GDP losses. For Australia, every sustained $1 rise in a barrel of oil adds roughly 1 cent per litre at the pump, though the effect is amplified by the weaker Australian dollar and refinery margins.

The mining sector, which consumes up to 40% of national diesel, faces particular strain. Farmers and logistics operators are already reporting higher costs flowing through to food prices and freight rates. Regional service stations have imposed informal limits or run dry at times, prompting calls for coordinated industry action. The Australian Competition and Consumer Commission granted interim authorisation for fuel suppliers to share information and manage supply disruptions.

Motorists are feeling the pinch. The NRMA and Australian Automobile Association have urged drivers to shop around using fuel apps, avoid topping up unnecessarily and consider fuel-efficient routes. Some analysts warn that without swift resolution, retail prices could test $2.50–$3.00 a litre in coming weeks, adding hundreds of dollars annually to household budgets already strained by cost-of-living pressures.

The government has ruled out immediate rationing but has not dismissed the possibility if the crisis worsens. Temporary easing of fuel quality standards and diplomatic efforts to secure alternative supplies, including closer cooperation with Singapore, are under discussion. Australia has joined international statements supporting freedom of navigation in the strait but has declined to send naval vessels.

Longer-term vulnerabilities are now impossible to ignore. Successive governments have allowed domestic refining capacity to shrink, leaving the nation almost entirely dependent on imported refined products. Rebuilding sovereign refining capability would cost billions and take years. Calls are growing for accelerated investment in strategic reserves, diversification of supply sources and faster transition to electric vehicles and renewables to reduce oil dependence.

For now, the immediate risk is not nationwide empty pumps but sustained high prices, regional shortages and economic ripple effects. The mining-heavy economy, export-driven agriculture and vast distances between population centres make Australia unusually exposed to global fuel shocks despite its geographic distance from the Middle East.

As President Donald Trump extends deadlines for potential strikes and Iran maintains its hard line, markets remain on edge. Any escalation that further restricts tanker flows could exhaust Australia’s reserves faster than expected and force tougher choices between keeping essential services running and protecting household budgets.

The “Strait” jacket tightening around Australia’s fuel supply serves as a stark reminder of the country’s energy insecurity. With reserves measured in mere weeks rather than months, even a partial or temporary disruption carries outsized consequences. How quickly diplomacy or military action reopens the chokepoint will determine whether this shock remains a painful spike or becomes a deeper crisis that freezes parts of the economy.