The US-Israeli war on Iran is in its third week with no end in sight.
The critical Strait of Hormuz, through which 20 per cent of the world's oil and liquefied natural gas flow, remains largely closed off, raising energy prices and fears of inflation.
The conflict has already imposed economic costs on US allies, who were not consulted before the airstrikes on Iran and who have endured months of harsh criticism and bellicose threats from Trump since he returned to office.
A number of US partners, including Germany, Spain and Italy, said they had no plans to send ships to help reopen the strategic waterway, which Iran has effectively shut with drones and naval mines.
"We lack the mandate from the United Nations, the European Union or NATO required under the Basic Law," German Chancellor Friedrich Merz said in Berlin.
Trump, speaking at a White House event in Washington on Monday, said many countries had told him they were prepared to help, but voiced frustration with some long-standing allies.
"Some are very enthusiastic about it, and some aren't," he said.
"Some are countries that we've helped for many, many years. We've protected them from horrible outside sources, and they weren't that enthusiastic. And the level of enthusiasm matters to me."
There was no let-up in attacks by both sides early on Tuesday, with the Israeli military saying it had begun a "wide-scale wave of strikes" across Iran's capital targeting "Iranian regime infrastructure", as well as Hezbollah sites in Beirut, a day after saying it had drawn up detailed plans for at least three more weeks of war with Iran.
Iran launched overnight attacks on Israel, underscoring that, more than two weeks into the war, Tehran still retains the capacity to carry out long-range strikes.
It also targeted the United Arab Emirates, where attacks forced the temporary closure of airspace and a drone hit an oil facility in Fujairah, a key port for Emirati oil exports, for a second consecutive day.
On Monday, Dubai International Airport was closed for several hours; oil loading operations in Fujairah were halted, and operations at the Shah gas field in Abu Dhabi were suspended following drone strikes.
The snap announcement on its airspace showed the balancing act Emirati authorities face in trying to keep their long-haul carriers, Emirates and Etihad, flying as Iranian attacks continue to target the country.
Iran has said that a US attack over the weekend on military sites at Kharg Island, a key hub for the country's oil exports, was launched from the UAE, and warned that it would target oil and gas facilities in any country from which US strikes on the island were carried out.
Iran has also said that it would target US industrial facilities in the Middle East and urged people living near US-owned plants to leave.
Rockets and at least five drones also targeted the US embassy in Baghdad early on Tuesday, Iraqi security sources said, describing it as the most intense assault since the war began. Two US officials said no injuries were reported so far.
Trump said earlier on Monday that Iran's retaliatory strikes against its neighbours including Qatar, Saudi Arabia, the United Arab Emirates, Bahrain and Kuwait were a surprise.
"They (Iran) weren't supposed to go after all these other countries in the Middle East," he said.
"Nobody expected that. We were shocked."
However, Trump was warned that attacking Iran could trigger retaliation against US Gulf allies, according to a US official and two sources familiar with US intelligence reports.
Oil prices rose more than two per cent in early trade on Tuesday, reversing some of the previous session's losses, on worries about supply, while Asian shares also rallied after Monday's sell-off.
The war has killed at least 2000 people across the Middle East since the US and Israel attacked Iran on February 28, including at least 200 children in Iran, according to Iranian Foreign Minister Abbas Araqchi.
Thirteen US troops have been killed and the number injured has risen to about 200.
with AP
