(FOX NEWS) — President Donald Trump said Thursday that Iran has agreed both to forgo nuclear weapons and to return material buried deep underground following recent U.S. military action, describing the development as a significant step forward in a high-stakes standoff.

Speaking to reporters before departing for Las Vegas, Trump also confirmed Iran had “agreed” the nation would not have a nuclear weapon and very “powerfully.”

“The big thing we have to do is we have to make sure that Iran does not have a nuclear weapon, because if they do, you want to talk about problems, you’d have problems,” the president said.

“So very important is that Iran does not have a nuclear weapon, and they’ve agreed to that. Iran has agreed to that, and they’ve agreed to it very powerfully.”

“They’ve agreed to give us back the nuclear dust that’s way underground because of the attack we made with the B-2 bombers. So we have a lot of agreement with Iran, and I think something’s going to happen.”

Trump also stated that it was a “very positive, very complicated subject.”

“I don’t think we’re waiting. I think we’re moving very fast. It could happen pretty quickly,” he confirmed.