Trump issued the warning in a social media post on Saturday, saying Washington would “obliterate” Iranian power facilities if the strategic waterway remained closed. The strait, a critical conduit for global oil flows, has been effectively shut amid the ongoing hostilities.

Iran’s military command, Khatam al-Anbiya, said any attack on its fuel and energy infrastructure would trigger strikes on U.S. and Israeli assets, including critical civilian-linked systems.

The statement, carried by state media, underscored a widening scope of potential targets beyond conventional military sites.

Iranian officials also indicated that access through the Strait of Hormuz would be restricted, with passage permitted selectively, reflecting Tehran’s control over the route during the conflict.

The escalation coincided with renewed Iranian missile barrages on Israel, including strikes near the southern cities of Dimona and Arad, close to the Negev Desert nuclear research area.

Israeli authorities said dozens were injured and residential buildings sustained heavy damage.Israeli Prime Minister Benjamin Netanyahu said the impact in Arad caused extensive destruction but no fatalities, while urging adherence to air raid warnings. Israel’s military acknowledged that some missiles were not intercepted, marking a breach in air defence coverage in the area.

Iran’s parliament speaker Mohammad Bagher Ghalibaf said the strikes indicated a shift to a new operational phase in the conflict.

The conflict has extended beyond Iran and Israel, with Hezbollah claiming responsibility for a deadly strike in northern Israel, while Gulf states reported drone and missile activity targeting energy infrastructure.

Iran also targeted the joint UK-U.S. military facility at Diego Garcia in the Indian Ocean, though officials said the strike was unsuccessful. Military assessments cited in reports suggested the possibility of longer-range capabilities or alternative launch methods, though no confirmation was provided by Tehran.

The disruption to shipping through the Strait of Hormuz has halted most tanker traffic, contributing to supply constraints and rising global energy prices. Countries including the United Arab Emirates, Britain, Germany, France and Japan have expressed readiness to support efforts to restore safe navigation through the waterway.

U.S. Central Command said earlier that strikes on Iranian coastal facilities had degraded Tehran’s ability to target vessels in the strait. Additional U.S. naval assets and personnel are being deployed to the region as part of ongoing operations.

Casualties have mounted across multiple theatres, with Iran reporting more than 1,500 deaths, while Israel, the United States and Gulf states have also recorded military and civilian losses.

Air raid sirens sounded across Israel early on Sunday, warning of incoming Iranian missiles, after dozens of people were wounded overnight in separate attacks in the southern towns of Arad and Dimona. Israel’s military said it was carrying out strikes on Tehran hours after the Iranian attacks.

Trump on Saturday warned he would “obliterate” Iran’s power plants if Tehran did not fully reopen the Strait of Hormuz within 48 hours, marking a sharp escalation a day after suggesting the conflict could be wound down.

Iran responded on Sunday by warning it would strike U.S. infrastructure, including energy facilities in the Gulf, if Washington followed through on its threat. The warning came as U.S. Marines and heavy landing craft continued moving toward the region.

The exchange of threats has heightened fears that energy installations across key Gulf producers could become direct targets, widening the conflict beyond current theatres of engagement.

The escalating the crisis has disrupted markets, pushing fuel costs higher and intensifying concerns over global inflation. Analysts said the situation has introduced acute uncertainty into financial markets already strained by supply disruptions.

“President Trump’s threat has now placed a 48-hour ticking time bomb of elevated uncertainty over markets,” said Tony Sycamore, an analyst at IG.

He warned that failure to de-escalate could trigger sharp declines in global equities and further spikes in oil prices.

Oil prices rose on Friday to their highest levels in nearly four years after Iraq declared force majeure on oilfields operated by foreign firms, Israel struck a major Iranian gas field, and Tehran retaliated with attacks on neighbouring countries including Saudi Arabia, the United Arab Emirates, Qatar and Kuwait.

Iranian actions have effectively closed the Strait of Hormuz, a narrow passage that carries around a fifth of global oil and liquefied natural gas supplies, triggering what analysts describe as the most severe oil disruption since the 1970s.

The near-closure has also driven European gas prices sharply higher, with increases of up to 35% reported last week, reflecting the strait’s central role in global energy flows.

In a social media post late on Saturday, Trump reiterated his ultimatum, saying the United States would begin targeting Iran’s power infrastructure if the waterway was not reopened “fully” and “without threat” within the specified timeframe.

In a social media post, Trump said the United States would “hit and obliterate” Iranian power infrastructure if the strait was not “fully open, without threat” within the deadline, broadening the potential scope of U.S. military action to include civilian-linked facilities.

The Strait of Hormuz is a critical maritime corridor through which roughly a fifth of global oil and liquefied natural gas flows. Ongoing threats and disruptions have deterred shipping traffic, with the near-blockade triggering a surge in European gas prices of up to 35% last week.Energy markets have remained volatile as the risk to Gulf infrastructure intensifies.

The situation worsened after Iran responded to an Israeli strike on one of its major gas fields by targeting Ras Laffan Industrial City in Qatar, a key hub processing a significant share of the world’s liquefied natural gas. Damage from the strike is expected to take years to repair, according to reports.

Iran warns of broader retaliationIran’s Khatam al-Anbiya military headquarters said on Sunday that any U.S. attack on its fuel and energy infrastructure would prompt retaliatory strikes on American energy, information technology and desalination assets across the region.

The exchange of threats underscores a widening confrontation that increasingly targets economic and civilian-linked infrastructure, raising the stakes for regional stability and global supply chains.Israeli officials said Iran had fired long-range missiles for the first time since hostilities intensified on February 28, expanding the potential reach of the conflict.

According to Israeli military chief Eyal Zamir, Iran launched two ballistic missiles with a range of about 4,000 km at the Diego Garcia base in the Indian Ocean.Zamir said the missiles’ range extended beyond the Middle East, placing European capitals within potential reach.

A source at Britain’s defense ministry said the attack occurred before London granted specific authorization on Friday for the United States to use British bases for strikes on Iranian missile sites.

The developments mark a significant expansion in both the geographic scope and strategic targets of the conflict, with direct implications for international energy flows and military alignments.