“They still have capacity. They have some missiles, they have some drones. I would say, percentage-wise, maybe 21, 22 per cent of their missiles,” Trump told NBC News in an interview.

That estimate for Iran’s remaining missile stockpile is higher than the 18 per cent Trump gave in May. He has often claimed to have completely destroyed Iran’s war-fighting capacity.

Iran’s military said on Friday it had fired “warning missiles” at two US destroyers in the Gulf of Oman — a claim promptly denied by the US military.

Two days earlier, Kuwait said it had intercepted 30 ballistic missiles fired as part of “heinous Iranian aggression.”

Weeks of complex talks marked by threats and flare-ups of violence have failed to secure a deal to end the war.

But Trump said Iran has “got no choice” except to reach an agreement.

“They’re strong, they’re proud, there are things they never thought they’d be doing that they’re going to have to do,” he told NBC.