US President Donald Trump has threatened further strikes against Iran on Monday after the first exchange of direct attacks in a month.
Iran launched missiles overnight at two US air bases in Jordan in response to a US attack on Iran's Larak Island, where Washington said it had struck Iranian launchers firing mines into the Strait of Hormuz.
While neither side appeared to be seeking a return to full-scale war, both signalled they were prepared to respond to further attacks.
"We're going to hit them hard," a Fox News reporter quoted Trump as later telling the channel. "There will be a response".
Separately, Trump told reporters in the Oval Office that the renewed strikes did not signal a return to full-scale war, describing Iran as a "failed nation" whose economy and military had been severely degraded. "That doesn't mean we won't smack them. We'll see what happens."
Asked whether he had ruled out using nuclear weapons against Iran, Trump said there was "no reason" to do so because Iran was already "totally defeated militarily".
Trump said US air defences had downed all Iranian missiles that could have caused any damage and that new US economic sanctions on Iran were having a big impact, Fox News reported.
Earlier, Trump had posted to social media two videos depicting explosions engulfing Iran's main oil export terminal, with the message "Kharg island being blown to smithereens!!!"
But the videos were AI-generated, and no such attack took place. Vice President JD Vance told reporters Trump "likes to switch it up on social media a little bit" and was "sending a message".
Washington has so far mainly held off from hitting Iran's major oil and gas infrastructure, a move that Iran says would be met with devastating attacks against its Gulf neighbours.
PILING ON ECONOMIC PRESSURE
Instead, Washington has stepped up efforts to punish Tehran and its business partners with "secondary sanctions" that hit third countries buying its oil.
US Treasury Secretary Scott Bessent said that Iran was "lashing out" now because the new sanctions were taking a toll on its economy.
"They're in shock at the state of their economy," Bessent told reporters at a meeting of G20 finance ministers and central bank governors in North Carolina. "I would think that they are lashing out kinetically because they are losing economically."
Bessent told Reuters on Sunday that new secondary sanctions were likely to be unveiled weekly in the effort to pressure Iran, with an initial focus on banks.

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