Trump just announced that he’s instructed Steve Mnuchin to ratchet up the sanctions on Iran:
I have just instructed the Secretary of the Treasury to substantially increase Sanctions on the country of Iran!
— Donald J. Trump (@realDonaldTrump) September 18, 2019
While Trump doesn’t go into detail, this appears to be in response to the attack on Saudi Arabia’s oil refinery.
Some had wondered if Trump would use military force in response to the attack.