The US president insists Washington has already decimated Tehran in a "very conventional way"

Donald Trump has lashed out at a reporter who asked whether his threats to destroy Iranian power plants, bridges, and the entire civilization meant he was ready to use a nuclear weapon, dismissing the question as "stupid."

The exchange took place at the White House on Thursday, where a journalist recalled Trump's April 7 warning that "a whole civilization will die tonight, never to be brought back again" if Tehran did not accept his terms, a remark widely condemned as apocalyptic and potentially genocidal.

"Why would a stupid question like that be asked? Why would I use a nuclear weapon when we've totally, in a very conventional way, decimated them without it? No, I wouldn't use it," Trump said, adding that a "nuclear weapon should never be allowed to be used by anybody."

The US president used the occasion to once again boast about the scale of US military damage inflicted on Iran, while suggesting that any rearmament by Tehran during the ceasefire could be knocked out in "about one day" if necessary. He also said he could make a deal immediately, but wanted one that was "everlasting."

"I want to make the best deal. I could make a deal right now... but I don't want to do that. I want to have it everlasting," Trump said.

Washington indefinitely extended the ceasefire earlier this week, expecting a "unified" proposal from Tehran, while keeping the US blockade of Iranian ports in place, even as follow-up talks with Tehran stalled and tensions persisted around the Strait of Hormuz.

Trump has made clear there is no firm timeline for ending the war, telling Fox News on Wednesday that there was "no time frame," and urging critics not to "rush" him again on Thursday.

The Iranian military, meanwhile, said it was prepared to fight the US "until complete victory." Parliament speaker Mohammad Bagher Ghalibaf accused the US of trying to turn negotiations into "a table of surrender," adding that talks and a "complete ceasefire" would only make sense if they were not violated by the maritime blockade.

"They did not achieve their goals through military aggression, nor will they through bullying. The only way forward is to recognize the rights of the Iranian nation," Ghalibaf wrote on X on Thursday.