US President Donald Trump has warned Iran against continuing activities at what is supposed to be an Iranian underground nuclear facility near Natanz, otherwise the United States will “hit them very hard.”

“We notice there's a little activity at Pickaxe. I would advise Iran not to get cute because we will have to hit them very hard. We have no choice,” he told the Republican midterm convention in Texas.

“We may have to give them a shot there (at Pickaxe Mount – TASS) too because somebody said there was a little movement at the site,” he added.