Tehran (AFP) - Iran on Thursday threatened “crushing” attacks on the US and Israel, firing missiles at Tel Aviv after US President Donald Trump vowed to bomb the Islamic republic “back to the Stone Ages”.

The war, which erupted more than a month ago with US-Israeli strikes on Iran, has spread throughout the Middle East and roiled the global economy, impacting hundreds of millions of people worldwide.

In a prime-time White House address, Trump said the US was “very close” to achieving its objectives but warned attacks would intensify if Iran did not reach a negotiated settlement.

“Over the next two to three weeks, we are going to bring them back to the Stone Ages, where they belong,” he said.

Iran’s response was immediate, with Israeli air defences pressed into action and police responding to “several” impact sites, as four people were reportedly lightly injured in the Tel Aviv area.

The war continues to disrupt oil and shipping, with British Foreign Minister Yvette Cooper stressing the “urgent need” to reopen the Strait of Hormuz, where one-fifth of the world’s oil usually passes.

While Trump has urged oil-importing countries to seize the waterway – virtually closed since the war began – French President Emmanuel Macron said Thursday a military operation to liberate the strait was “unrealistic”.

In Tehran, AFP journalists reported a series of loud explosions hitting the Iranian capital, shaking buildings and sending reverberations across the city. The targets were unclear.

The country’s two largest steel plants have meanwhile been forced offline by several waves of US and Israeli attacks, the companies said.

Despite the bombardments, Iranian families gathered at Tehran’s Melat park for the 13th day after Nowruz, the Persian New Year, when people traditionally picnic outdoors, AFP journalists said.

In Israel, Jewish Israelis were also celebrating Passover, which some were forced to do underground due to Iran’s attacks.

“This is not my first choice,” said a writer who gave his name as Jeffrey, at a meal organised in a Tel Aviv bunker.

- ‘Resist until the end’ -

Trump has repeatedly raised the prospect of a deal to end the war that has driven fuel prices higher in the US and around the world, and dented his approval ratings.

He said talks could be possible with Iran’s new leadership, which he described as “less radical and much more reasonable” than their predecessors.

But Tehran has dismissed Washington’s ceasefire overtures, describing US demands to end the conflict as “maximalist and irrational”.

“Messages have been received through intermediaries, including Pakistan, but there is no direct negotiation with the US,” said Iranian foreign ministry spokesman Esmaeil Baqaei, quoted by the ISNA news agency Thursday.

Trump warned that if no agreement with Tehran was struck, Washington had “our eyes on key targets including the country’s electric generating plants”.

Pro-government Iranians voiced defiance as they marched in Tehran at the funeral of a Revolutionary Guards naval commander killed in an Israeli strike.

“This war has lasted a month. However long it takes, we will continue,” said Moussa Nowruzi, a 57-year-old pensioner.

“We will resist until the end.”

The country’s health ministry said the Pasteur Institute of Iran, a century-old medical centre in Tehran, had been extensively damaged in a strike.

In Lebanon, militant group Hezbollah said its fighters launched drones and rockets at northern Israel Thursday, with the Israeli military’s Home Front Command saying air raid sirens were activated.

A day earlier, Israel killed a top Hezbollah commander, two sources told AFP, in a Beirut strike that the Lebanese health ministry said killed seven people.

Authorities in Lebanon say Israeli attacks have killed more than 1,300 people in the country since war erupted between Israel and Iran-backed Hezbollah on March 2.

- ‘Oxygen for volatility’ -

The conflict has drawn in Gulf countries once seen as a safe haven in a volatile region, with air defences in the United Arab Emirates responding to missile and drone threats Thursday.

The war has also highlighted the importance of the Strait of Hormuz.

Iran’s Revolutionary Guards have vowed to keep it shut to the country’s “enemies” while Trump has made reopening it a condition for a ceasefire.

China is a major importer of oil through the shipping lane. Its foreign ministry blamed the United States and Israel for being the “root cause” of the blockage.

Trump’s speech did nothing to reassure markets, as oil prices spiked and stocks tumbled.

The World Bank’s Managing Director Paschal Donohoe told AFP the institution was “extremely concerned” about the war’s impact on inflation, jobs and food security.

The economic fallout is being felt worldwide, with airlines in China saying they will hike fuel surcharges and Malaysian civil servants being asked to work from home.

Even the Himalayan kingdom of Bhutan is feeling the impact, with the government saying “external conditions beyond our control” had forced a hike in fuel prices.

AFP reporters in the capital Thimphu saw long queues at filling stations Thursday amid shortages in the landlocked nation of around 800,000 people.

“I don’t know what to say. It’s not like our government is responsible, they are trying their best despite the war in the Middle East and price hike in India,” said Karma Kalden, 40, a Thimphu resident.

“We are helpless.”

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