Iranian military rockets in museum, Tehran, Iran
Iranian military rockets in museum, Tehran, IraniStock

A top Iranian military official warned on Saturday of a "heavy price" for aggressors, following reports of US and Israeli plans for possible military drills to prepare for strikes against Iran's nuclear sites if diplomacy fails.

"Providing conditions for military commanders to test Iranian missiles with real targets will cost the aggressors a heavy price," said the military official, who was not named, as quoted by Reuters.

The comments came after a senior US official said this week that Defense Secretary Lloyd Austin and Defense Minister Benny Gantz would discuss possible military exercises that would prepare for a worst-case scenario to destroy Iran's nuclear facilities should diplomacy fail.

Austin and Gantz met at the Pentagon on Thursday amid the renewed nuclear talks between Iran and world powers, with both saying they would expand cooperation in the face of the Iranian threat.

White House Press Secretary Jen Psaki told reporters after the meeting that the United States is preparing "additional measures" against Iran should the nuclear talks not succeed.

"The president has asked his team to be prepared in the event that diplomacy fails and we must turn to other options," said Psaki.

"We will have no choice but to take additional measures," she added.