The United States will end its war on Iran fairly soon and could return for "spot hits" if needed, US President Donald Trump said, hours before he was scheduled to make a prime-time address to his nation.Trump also said he would state in the speech, which is due at 12pm AEDT Thursday (9pm Wednesday local time), that he was considering withdrawing the US from the North Atlantic Treaty Organization (NATO).Asked when the United States would consider the Iran war over, Trump said: "I can't tell you exactly .. we're going to be out pretty quickly."He was expected to reiterate a two-to-three-week timetable for ending the war in Iran during the address, a White House official later said.US action had ensured Iran would not have nuclear arms, Trump said: "They won't have a nuclear weapon because they are incapable of that now, and then I'll leave, and I'll take everybody with me, and if we have to we'll come back to do spot hits."An Iranian official, Mehdi Tabatabai, said in a post on X that an important letter to the American people from Iran's President Masoud Pezeshkian would be released "in a few hours".Global oil supplies were expected to be hit twice as hard this month as in March, the International Energy Agency said on Wednesday, underlining the urgent need for an end to the conflict Trump started alongside Israel on 28 February.Trump said separately on social media that Iran had asked for a ceasefire but that he would not consider it until Iran ceased blocking the Strait of Hormuz, a major fuel shipment route