US President Donald Trump declared on Monday that the United States will impose a 25% tariff on any country doing business with Iran.
"This Order is final and conclusive. Thank you for your attention to this matter!" Trump wrote in a post on his Truth Social platform.
Trump has repeatedly warned Iran in recent days that the US would hit hard at the Islamic Republic if it shoots anti-regime protesters.
On Sunday, the President told reporters that the US is watching Iran closely and weighing possible responses as unrest in the country grows.
Speaking to reporters aboard Air Force One, Trump stated that Iran is starting to cross his red line.
“There seems to be some people killed that aren't supposed to be killed. We are looking at it very seriously, the military is looking at it and we're looking at some very strong options," he added, noting that he is receiving reports on the Iranian protests every hour.
He also warned Iran against attacking American bases in the region, stating that if they do, “we will hit them harder than they imagined."
On Monday, White House Press Secretary Karoline Leavitt said that while Trump generally prefers diplomatic solutions, he has not ruled out the use of force against Iran.
“The truth is, with respect to Iran, nobody knows what President Trump is going to do except for President Trump. The world can keep waiting and guessing," she said.
Leavitt later told reporters that Iran’s public rhetoric does not necessarily reflect its private communications with Washington. She said the President has an interest in examining those private messages as he weighs his options.