As the war entered its seventh day, Israel’s military said it was striking Tehran and other parts of Iran, but all eyes were on whether Washington would enter the fray.
Iran’s supreme leader Ayatollah Ali Khamenei, meanwhile, rejected Trump’s demand for an “unconditional surrender”, despite claims from the US leader that “Iran’s got a lot of trouble and they want to negotiate”.
Trump has left his intentions on joining the conflict deliberately ambiguous, saying on Wednesday: “I may do it, I may not do it. I mean, nobody knows what I’m going to do.”
“The next week is going to be very big,” he added.
The White House said Trump would receive an intelligence briefing on Thursday, a US holiday. Top US diplomat Marco Rubio, meanwhile, will meet his UK counterpart for talks expected to focus on the conflict.
“I have ideas as to what to do, but I haven’t made a final [decision],” Trump said. “I like to make the final decision one second before it’s due, because things change. Especially with war.”
The Wall Street Journal reported that Trump had told aides on Tuesday he had approved attack plans but was holding off to see if Iran would give up its nuclear programme.
Trump has said Iranian officials “want to come to the White House”, a claim denied by Tehran.
The US president had favoured a diplomatic route to end Iran’s nuclear programme, seeking a deal to replace the agreement he tore up in his first term.
But since Israeli Prime Minister Benjamin Netanyahu unleashed the campaign against Iran one week ago, Trump has stood behind the key US ally.
The United States is the only country with the “bunker buster” bombs needed to destroy Iran’s Fordow nuclear plant, but US military action is deeply unpopular with parts of Trump’s base.
Khamenei on Wednesday insisted Iran “will never surrender,” and called Trump’s ultimatum “unacceptable”.
“America should know that any military intervention will undoubtedly result in irreparable damage,” Khamenei added.
A week of strikes has significantly degraded Iran’s nuclear and military installations, including buildings making and testing centrifuge components in Karaj and Tehran.
Centrifuges are vital for uranium enrichment, the sensitive process that can produce fuel for reactors or, in highly extended form, the core of a nuclear warhead.
Iran theoretically has enough near-weapons-grade material, if further refined, for more than nine bombs, but it denies seeking nuclear weapons.
Israel has maintained ambiguity on its own atomic activities, but the Stockholm International Peace Research Institute says it has 90 nuclear warheads. (AFP)