WASHINGTON: US missiles struck targets across Iran on Friday (Jul 24) and President Donald Trump vowed "major military punishment" for Tehran and its Houthi allies in Yemen, though he once again left open the door to a diplomatic deal with Iran.

Two weeks after the collapse of an interim truce meant to end the war, the Iranian armed forces responded by firing at US bases in neighbouring Arab countries and warning people there that they could strike non-military buildings used by US personnel.

Trump has threatened in recent days to expand the targets being struck in Iran to include energy plants and bridges, to send ground forces to seize its Kharg Island oil hub and to bomb a deep-underground nuclear-linked site known as Pickaxe Mountain.

On Friday, he said he had not yet made a decision for new major strikes.

"We are talking to them. I think they're being serious. I think ... they are being by far the most serious that we've seen them, but that doesn't mean we get there," Trump told reporters at the White House.

Asked what is the exit strategy for the Iran war, Trump said: "There's a military exit where we just keep going just the way we are, and we can even make it a heavier dose, and it's knocking out everything they have. Or there's a smarter strategy that you make a deal."

But he added: "We're locked and loaded. We're ready to go."

The entrance to the Gulf has so far been the focus of a war that has killed thousands in almost five months, stoked global inflation and fanned fears of an economic downturn.

The Houthis, who control northern and western Yemen, have announced a naval blockade on Saudi Arabia, which has diverted millions of barrels of oil each day by pipeline to the Red Sea to skirt Iran's near-total blockade of the Strait of Hormuz.

After the Houthis said they had struck two Saudi tankers on Thursday, Trump said he would hold Iran accountable for any further attacks by the fighters.

On Friday, several strikes hit Yemen's Hodeidah port, eyewitnesses said.

The Saudi-led coalition in Yemen said it carried out a "proportionate military response operation" that targeted Houthi military sites in Hodeidah governorate.

IRAN THREATENS US FORCES

The US military launched air strikes on Iran late on Thursday and early on Friday, for a 13th consecutive night of attacks, prompting Iran to fire at neighbouring Arab countries that host US bases.

US missiles struck a Revolutionary Guards Navy headquarters in the Ziba Kenar area of the Caspian Sea province of Gilan, according to a security official in Gilan quoted by Iranian media.

Provincial authorities said US projectiles had also struck the port city of Bandar Anzali, according to the ILNA news agency.

Four people were killed and five injured in a US attack on the Iranian city of Ahvaz, the state broadcaster IRIB said.

In a statement carried by Iran's Fars news agency, the Revolutionary Guards warned the populations of Gulf countries of potential strikes against US military personnel who may be using "buildings in cities as locations to direct their crimes".

Trump told Axios on Thursday he was considering relaunching major combat against Iran.

"They haven't received enough pain yet," the US news outlet quoted him as saying. In a statement on X, the Iranian health ministry said 59 people had been killed and 666 wounded since the resumption of clashes with US forces in late June.

Iranian media cited the head of Iran's top joint military command as saying Iran would kill a member of the US forces for every Iranian killed.

The war has killed 18 US service members. The Pentagon said on Monday that 100 service members had been injured since Jul 7 and 96 per cent have returned to duty.

Officials have told Reuters that more than 500 US troops have been injured so far.

PAKISTAN EXPLORING PATH FOR TALKS, SOURCES SAY

The attack on the Saudi tankers on Thursday in the Red Sea's Bab el-Mandeb Strait boosted oil prices 7 per cent to top US$100 per barrel for the first time since May.

However, by around 4pm GMT on Friday, Brent futures were down more than US$4 to a little over US$96.

Sources said Pakistan was exploring a path towards a resumption of stalled talks between the US and Iran over ending the war, following a push initiated by China.

Exploratory discussions took place during a visit by Iran's Interior Minister Eskandar Momeni to Islamabad this week - his second within the last 10 days, three Pakistani sources said.

TANKERS REROUTING, SHIPPING INSURANCE RISES

The Houthi attacks forced several other tankers to turn around and head north through the Suez Canal, potentially using a much longer route to reach Asia by sailing around Africa.

Shipping insurance costs through the southern Red Sea doubled for some companies on Thursday, sources said.

Still, half of the 18 ships exiting Bab el-Mandeb on Thursday were carrying crude oil, including two Chinese supertankers.

The number of tankers crossing through the Strait of Hormuz fell to just one on Thursday, the lowest since May 7.

US WARNS CITIZENS IN MIDEAST TO EXERCISE CAUTION

The Iranian army said it had attacked US military equipment depots at Al-Adiri, officially named Camp Buehring, in northern Kuwait, and the positions of US troops at Camp Arifjan and at Camp Doha, near Kuwait City.

In the early evening, Kuwait said its air defences were intercepting "hostile" targets launched from Iran.

Iran's Revolutionary Guards said they had significantly damaged a surveillance tower used by the US Fifth Fleet in Bahrain.

They also said they had attacked a US barracks and fighter jets in Jordan, and a US barracks and spy balloon as well as Patriot air defences in Erbil in Iraq's Kurdish region, according to the semi-official Tasnim news agency.

Jordan's army said it had downed seven Iranian missiles and six drones, state TV reported, and that the attack had caused no material damage or casualties.

The US embassy in Baghdad said US citizens in the Middle East should exercise caution and remain on heightened alert.