With global energy prices on the rise, Trump said the US Navy was ready to escort oil tankers through the Strait of the Hormuz, the vital chokepoint into the Gulf that Iran has threatened to seal off.

Risking more regional chaos, an Iranian drone attack struck near the US consulate in Dubai, starting a fire but inflicting no casualties, and the US military base at Al-Udeid in Qatar.

The attacks came a day after strikes on the US embassies in Riyadh and Kuwait City and on a US air base in Bahrain, as Washington ordered diplomats to evacuate.

"We are saying to the enemy that if it decides to hit our main centres, we will hit all economic centres in the region," Islamic Revolutionary Guard General Ebrahim Jabbari said.

The United States and Israel launched the attack on Saturday and quickly killed Iran's supreme leader, Ayatollah Ali Khamenei, two days after US envoys had been speaking to Iran in Geneva on a nuclear accord.

Trump insisted that Iran wanted to resume talks but it was "too late".

He also walked back a statement the day before from Secretary of State Marco Rubio, who said the US attack's timing was precipitated by Israel's plans to strike.

"If anything, I might have forced Israel's hand," Trump said as he met German Chancellor Friedrich Merz at the White House.

Trump boasted that "just about everything's been knocked out" in Iran, including its navy, air force and air detection, and said the attacks had killed even leaders who could have taken over.

"Most of the people we had in mind are dead," Trump said. "Now we have another group. They may be dead also, based on reports."

According to Iranian media, US and Israeli strikes targeted a building on Tuesday in the holy city of Qom belonging to the committee that is to elect a new supreme leader. The Tasnim news agency reported that strikes had already targeted the body's main headquarters in Tehran the day before.

- Lebanon violence expands -

The regional war also took a growing toll on Lebanon, where Hezbollah, the armed Shiite Muslim movement that long had Tehran as a benefactor, launched drones and rockets at Israel in retaliation for Khamenei's slaying.

Hezbollah said it targeted the Israeli naval base in the northern city of Haifa and Israel said it struck Beirut's heavily Shiite southern suburbs.

The United Nations said that more than 30,000 people were displaced in Lebanon, where dozens have been reported dead.

In a throwback to earlier wars, Israel said it was moving troops across the border to create a buffer zone inside Lebanon.

Loud explosions again hit Tehran, where photos showed damage to Mehrabad airport, which handles mainly domestic flights in Iran.

The Israeli military announced a strike on an underground facility on the eastern outskirts of Tehran where it said Iranian "scientists operated covertly to develop a key component for nuclear weapons".

Iran's foreign ministry spokesman said the UN Security Council "has a duty" to act to stop the war, even as its military remained publicly defiant in the face of the campaign.

Iran has vowed to take an economic toll in retaliation for the war and to make the United States pay a cost.

The United States ordered non-emergency personnel to leave embassies in much of the region and encouraged all Americans to leave if they can find commercial flights, although air travel has been severely disrupted.

Qatar said it had downed missiles targeting Hamad International Airport in Doha, while Oman reported several drones attacking the port of Duqm, and in the UAE falling debris from an intercepted drone caused a fire at an oil storage and trading zone, authorities said.

- Ghost town -

In Tehran, residents who have not fled remained shut away in their homes for fear of the US-Israeli bombardment.

The Iranian capital is normally home to around 10 million people, but in recent days "there are so few people that you'd think no one ever lived here", said Samireh, a 33-year-old nurse.

Authorities had previously urged people to leave the city, and police officers, armed security forces and armoured vehicles have been stationed at main junctions, carrying out random checks on vehicles.

In the more upmarket north of Tehran, the meowing of cats and chirping of birds replaced the usual din of traffic jams.

The assault came weeks after Iranian authorities clamped down on mass protests, although Trump has said that regime change is not his main goal.

Israel's Foreign Minister Gideon Saar urged foreign capitals on Tuesday to cut all ties with Tehran "following the Iranian regime's attacks on all its neighbours and the massacre of its own people".

China's Foreign Minister Wang Yi, according to the official Xinhua news agency, warned Saar in a call that Beijing opposes the strikes, saying the use of force "will only bring new problems".

burs/sct/msp

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