Iran's Supreme Leader Ayatollah Ali Khamenei said that if the US attacked Iran it would become a regional conflict, state media has reported, amid heightened tensions between Washington and Tehran.

"(Iran is) talking to us, and we'll see if we can do something, otherwise we'll see what happens ... We have a big fleet heading out there," Trump told Fox News.

"(Iran is) talking to us, and we'll see if we can do something, otherwise we'll see what happens ... We have a big fleet heading out there," Trump told Fox News.

Iran reports progress in U.S. negotiations amid rising tensions, with officials urging dialogue over military conflict.

US president says he hopes Iran will agree to give up nuclear weapons program; Iranian president says broader conflict will hurt both countries, not in anyone's interest