Trump has dispatched Vice President JD Vance to Pakistan to meet with top Iranian officials in a bid to reach a peace deal following a two-week ceasefire that was agreed on Tuesday.

"We're going to open up the Gulf with or without them...or the strait as they call it. I think it's going to go pretty quickly, and if it doesn't, we'll be able to finish it off," Trump told reporters as he left Washington for a domestic trip.

"We will have that open fairly soon."

The reopening of the Strait of Hormuz, through which one fifth of the world's crude passes, will loom large in the peace talks in Islamabad.

But when asked what a good deal would look like, Trump said: "No nuclear weapon. That's 99 percent of it."