Tehran, Iran - Iran said on Tuesday it was prepared for any eventuality, after US President Donald Trump warned "a whole civilization will die" if the Islamic republic did not heed a looming deadline to open the Strait of Hormuz.
Speaking in Budapest, Vice President JD Vance said the US had tools "that we so far haven't decided to use" against Iran, without explaining further.
The White House later denied Vance was alluding to nuclear weapons, while Press Secretary Karoline Leavitt said in a statement to AFP that "only the President knows where things stand and what he will do."
The statements came as Iran reported the US and Israel had begun striking key infrastructure, with Israeli Prime Minister Benjamin Netanyahu confirming attacks on railways and bridges he said were "used by the Revolutionary Guards."
Trump had initially vowed to carry out the "complete demolition" of Iran's critical infrastructure, particularly bridges and power plants, only if a deal was not reached by midnight GMT.
But hours before the deadline, the Israeli military said it had already completed a broad wave of strikes targeting "infrastructure sites" across Iran.
Writing on Truth Social, Trump elevated his ultimatum for Iran, stating that "a whole civilization will die tonight, never to be brought back again. I don't want that to happen, but it probably will."
It was not clear exactly what he meant by his latest threat, or by what means he intended to carry it out.
Hours ahead of the deadline, Iranian First Vice President Mohammad Reza Aref said his government was prepared "for all scenarios."
"No threat is beyond our preparedness and intelligence," he added.
Both Trump and Iran have turned down a proposal touted by international mediators for a 45-day ceasefire.
Infrastructure attacks reported by Iranian authorities Tuesday included a US-Israeli strike on a bridge outside the city of Qom and another on a rail bridge in central Iran that killed two people.
Regional authorities also said a US-Israeli strike shut down a key highway in northern Iran connecting the city of Tabriz with Tehran.
The Mizan news agency additionally reported a strike on railway tracks in Karaj, outside Tehran.