US President Donald Trump has threatened to “massively blow up” Iran’s “entire” gas fields if it launches any more attacks on its Gulf neighbours in retaliation to Israel.

Israeli hit Iran’s section of the world’s largest gas field in a major escalation of the war, sending oil prices up again.

Tehran lashed out on Thursday (AEDT), striking Qatar, firing missiles at Saudi Arabia and vowing to attack oil and gas targets in payback.

Trump said the US had not been aware of Israel’s plan to target Iran’s energy production facilities.

The president promised that another attack on the gas field would not happen again.

He said Israel’s strikes were “anger for what has taken place in the Middle East”.

“NO MORE ATTACKS WILL BE MADE BY ISRAEL pertaining to this extremely important and valuable South Pars Field unless Iran unwisely decides to attack a very innocent, in this case, Qatar,” Trump posted to Truth Social.

“In which instance the United States of America, with or without the help or consent of Israel, will massively blow up the entirety of the South Pars Gas Field at an amount of strength and power that Iran has never seen or witnessed before.

“I do not want to authorise this level of violence and destruction because of the long term implications that it will have on the future of Iran, but if Qatar’s LNG is again attacked, I will not hesitate to do so.”

Qatar’s state oil giant QatarEnergy reported “extensive damage” after the Ras Laffan Industrial City, an energy-industry hub, was hit by Iranian missiles.

Saudi Arabia said it had intercepted and destroyed four ballistic missiles launched toward Riyadh and an attempted drone attack on a gas facility in ‌the east of the country.

The escalation threatens to worsen an unprecedented disruption to global energy supplies.

Benchmark Brent crude prices rose around five per cent to above $US108 ($153). Stock markets veered lower.

Pars is the Iranian sector of the world’s largest natural gas deposit, which Iran shares with Qatar across the Gulf.

Prime Minister Anthony Albanese said the attack on the gas plant was worrying.

“Quite clearly, this is a major concern, and the attack on the Qatari LNG facility, even though that was turned off at the time, what that will impact is future supply,” he said in Hobart on Thursday.

“We’ll continue to monitor all of these issues, but that’s why we call for a de-escalation.

“Qatar is not a participant in this conflict, but Iran has chosen to attack, unprovoked, 12 countries in the region, indeed countries that have not been participants.”

Fuel prices have soared globally as a result of one of the world’s major oil corridors — the Strait of Hormuz — being closed by Iran in response to the conflict.

While there has been no timeline on when the war would come to an end, Albanese said the goal of Tehran’s regime being denied its nuclear weapons potential had been achieved.

“I can see it (the war) ending, coming to an end, and us making sure that we get the world back on its normal axis,” he told Triple M radio.

“[There will be] a bit of a tail, though, like you don’t end the war, and then everything is all hunky dory.”

Qatar, a close US ally that hosts the largest US airbase in the region, blamed the attack on Israel, and called it “dangerous and irresponsible” that put global energy security at risk. The UAE also denounced the attack.

Iran listed an array of prominent regional oil ⁠and gas facilities it called “direct and legitimate targets” — Saudi Arabia’s Samref Refinery and Jubail Petrochemical Complex, the UAE’s Al Hosn Gas Field, and Qatar’s Mesaieed ‌Petrochemical Complex, Mesaieed Holding Company and Ras ​Laffan.

It said they should be evacuated at once before it struck them in the coming hours.

The US and Israel had previously held back from targeting Iran’s energy production facilities in the Gulf, averting Iranian retaliation against the oil and gas industries of ​its neighbours.

Iran has already shut ‌the Strait of Hormuz, which handles 20 per cent of global oil and liquefied natural gas supply, but consuming nations have hoped the disruption would prove short-lived as long as production infrastructure was spared.

-with AAP