Iran has issued a stark warning to the United States, vowing that any further military action will be met with a "faster, more intense and more painful response" — a sharp escalation in rhetoric following a weekend of mutual strikes on naval vessels in and around the strategically vital Strait of Hormuz.

Iranian negotiator Mohammad Baqer Qalibaf made the warning in a speech broadcast by state media, declaring that "the era of proportionate responses has come to an end." The comments came after both sides targeted each other's ships on Saturday in one of the most direct military confrontations since the conflict began in late February.

Weekend Clashes in the Strait of Hormuz

Saturday's exchange of fire saw Iran's Revolutionary Guard Corps claim strikes against a US naval drone, an aircraft carrier, a destroyer, and three oil tankers in the Strait of Hormuz. The US Central Command (CENTCOM), for its part, said its forces "disabled" two Iranian oil tankers near Iran's Kharg island and "completely destroyed" an unladen Iranian crude oil tanker in the Sea of Oman. CENTCOM added that American warships had "successfully evaded" Iran's attacks.

The clashes are the latest chapter in an intensifying struggle for control of the Strait, a chokepoint through which a significant share of the world's oil supply passes. Iran has largely blocked passage through the waterway since the outbreak of war on February 28. For background on the broader international reaction to the conflict, see the Reactions to the Twelve-Day War overview.

Washington responded to Iran's blockade by imposing a counter-blockade on Iranian ports, a strategy it publicly labelled an "economic asphyxiation" campaign last month, aimed at further straining Iran's already weakened economy.

Iran Announces New 'Prohibited Zone' Near the Strait

Iran's Secretary of the Supreme National Security Council, Mohsen Rezaei, announced on Sunday that a formal "prohibited zone" would be established near the Strait of Hormuz within days.

"In the coming days, a prohibited zone will be announced outside the Strait of Hormuz," Rezaei told state television. "This zone will start from the US Navy's blockade line and include areas of the Persian Gulf. Any ship entering this new zone will be placed on the sanctions list of Iran."

The announcement signals Iran's intent to formalise and extend its control over the surrounding maritime region, raising concerns about further disruptions to international shipping lanes. Those tracking the Hormuz crisis and its implications for regional escalation will note this marks a significant hardening of Iran's posture.

Economic Pressure and Fuel Price Hike

Alongside military posturing, Iran is moving to shore up its domestic economy against the impact of US sanctions. The Iranian government has announced it will raise gasoline prices for consumers who use more than 110 litres per month, beginning Tuesday.

Government spokesperson Fatemeh Mohajerani said the price of the first and second quota tiers — covering up to 110 litres — will remain unchanged. However, the third quota will be raised to 100,000 Iranian rials per litre, equivalent to roughly four US cents based on current free-market rates.

Under the new structure, motorists can still purchase up to 60 litres at 15,000 rials per litre and a further 50 litres at 30,000 rials per litre. Only usage beyond that threshold will attract the higher rate.

Mohajerani said the increase was due to "current conditions" — an apparent reference to wartime economic pressures. The government had previously considered and then postponed such a move amid fears it could reignite public unrest. Iran experienced widespread protests in 2019 triggered by a similar fuel price increase, and authorities remain sensitive to the political risks of revisiting the issue.

Iran's gasoline prices are among the lowest in the world, a legacy of decades of state subsidies. A partial price increase for most users had already been implemented in December, as the OPEC member sought to curb surging domestic fuel demand.

Economic Warfare and the Broader Conflict

Revolutionary Guard spokesperson Hossein Mohebi framed Iran's economic strategy in combative terms, saying Tehran was actively working to inflict financial damage on Washington.

"If America wants to inflict one dollar of economic damage on Iran, it inflicts tens of dollars of damage on itself," he said.

Qalibaf echoed that framing in his speech, calling on Iranian authorities to better manage imports to counter what he described as a US campaign "seeking to paralyse the supply cycle and energy management."

Meanwhile, the conflict's regional ripple effects are widening. In Yemen, more than 140 combatants were killed between midday Saturday and early Sunday morning in clashes between Saudi-backed government forces and Iran-backed Houthi rebels. Military sources indicated 84 government troops were killed — mostly in missile attacks — while 57 Houthi fighters also lost their lives. The fighting centres on control of a strategic gateway to the Red Sea, with the Houthis launching an offensive aimed at the port city of Mokha and territory bordering the Bab al-Mandab strait. Those clashes represent some of the deadliest fighting in Yemen since a 2022 ceasefire broke down in July.

With both sides showing no sign of backing down and Iran now threatening to formalise a maritime exclusion zone, the path to de-escalation in the Strait of Hormuz appears increasingly narrow. For the latest on diplomatic efforts, see our earlier coverage on what happens next following the US-Iran ceasefire.