President Trump has said he does not want war but warned Iran it would face “obliteration” if conflict broke out.
Speaking to NBC on Friday, he said the US was open to talks but would not allow Iran to develop nuclear weapons.
He also expanded on his last-minute decision to call off strikes planned in response to the shooting down of a US unmanned drone this week, saying he had been told 150 Iranians would be killed.
“I didn’t like it. I didn’t think it was proportionate,” he said.
Tehran says the unmanned US aircraft entered Iranian airspace early on Thursday morning. The US maintains it was shot down in international airspace
Tensions have been escalating between the two countries, with the US recently blaming Iran for attacks on oil tankers operating in the region. Iran has announced it will soon exceed international agreed limits on its nuclear programme.
Last year, the US unilaterally pulled out of a 2015 nuclear deal aimed at curbing Iran’s nuclear activities.
The US has now asked the UN Security Council to meet on Monday to discuss Iran.