US President Donald Trump has again said he expects a sharp drop in diesel fuel prices and a swift end to the standoff with Iran.

The American leader made the remarks at an event marking Columbus Day.

"I think we have important news on the diesel fuel situation. Do you remember what we did? We stopped Iran from acquiring nuclear weapons. Prices will go sharply down, and all of this will end soon — one way or another," he said.

According to the US president, this can be achieved in two ways.

"It's very simple. One way or another, it will all end very soon," Trump emphasized.

The American leader also said Iran no longer has an army, a navy or an air force, or air defense assets.