US President Donald Trump "believes firmly we cannot have a nuclear-armed Iran," Wright told reporters in Paris on the sidelines of meetings of the International Energy Agency.

"They've been very clear about what they would do with nuclear weapons. It's entirely unacceptable," Wright said.

"So one way or the other, we are going to end, deter Iran's march towards a nuclear weapon," he added.

US and Iranian officials held talks in Geneva on Tuesday aimed at averting the possibility of US military intervention to curb Tehran's nuclear programme.

Iran said following the talks that they had agreed on "guiding principles" for a deal to avoid conflict.

US Vice President JD Vance, however, said Tehran had not yet acknowledged all of Washington's red lines.