US President Donald Trump warned Tuesday that the United States may strike Iran again, a day after he claimed to have held off a major assault in hope of a deal to end the war – but Tehran's army threatened to open "new fronts" if he went ahead. Trump told reporters at the White House that he had been just "an hour away" from relaunching Washington's attacks on Iran before postponing the order, after weeks of a fragile ceasefire and talks to end the war that the US and Israel launched on February 28. "You know how it is to negotiate with a country where you're beating them badly. They come to the table, they're begging to make a deal," he said. "I hope we don't have to do the war, but we may have to give them another big hit. I'm not sure yet." Read moreMiddle East war live: Trump says US may hit Iran again, claims Tehran wants deal But Iran's army spokesman Mohammad Akraminia earlier warned the Islamic Republic would "open new fronts against" the United States if it restarted its attacks. He added that Iran's military had used the ceasefire as an opportunity "to strengthen its combat capabilities". Trump offered a deadline of several days for resuming strikes if a deal was not agreed. "I'm saying two or three days, maybe Friday, Saturday, Sunday, something, maybe early next week, a limited period of time," he said. 'Assault at a moment's notice' Trump's new deadline came after he said on Monday that Gulf leaders had asked him to hold off on an attack at the 11th hour, which he did because "serious negotiations are taking place". But if a deal was not agreed, he said he instructed the US military to be "prepared to go forward with a full, large-scale assault of Iran, on a moment's notice." Iran's Deputy Foreign Minister Kazem Gharibabadi wrote on X that Trump's comments meant the US leader was "calling a 'threat' a 'chance for peace'!" The US-Israeli bombing killed thousands of people in Iran before it was suspended in ​a ceasefire in early April. Israel has killed thousands more and driven hundreds of thousands from their homes in Lebanon, which it invaded in pursuit of Hezbollah after the Iran-backed group launched rockets across the border. Iranian strikes on Israel and neighbouring Gulf states have killed dozens of people. Trump had already indefinitely extended the truce and made clear he wants to exit a war that has proven to be a political liability. The US president is under intense political pressure at home to reach an accord that would reopen the ⁠Strait of Hormuz – a key route for global supplies of oil and other commodities that Iran has effectively closed off. Fuel prices remain high and Trump's approval rating has plummeted as congressional elections loom in November. Drone attack Since the ceasefire took hold on April 8, Tehran and Washington have held a single round of talks, which failed to culminate in a deal. Iran has repeatedly rebuffed Trump's offers on a deal and its control over the vital Hormuz strait has sent global oil prices spiraling. Iranian foreign ministry spokesman Esmaeil Baghaei confirmed exchanges with the United States through mediator Pakistan and said Tehran made clear its "concerns". The cleric-run state, which has remained resilient despite the US and Israeli killing 86-year-old supreme leader Ayatollah Ali Khamenei in the opening air strikes of the war, is demanding the release of Iranian assets frozen abroad and the lifting of long-standing sanctions.