US President Donald Trump has said countries doing business with Iran will face a 25% tariff on trade they do with America.
It comes as Iran cracks down on anti-government protests, with thousands of people feared dead.
Trump has used the threat of tariffs before to exert pressure on countries. Here's what we know so far.
On Monday Trump posted on Truth Social: "Effective immediately, any country doing business with the Islamic Republic of Iran will pay a tariff of 25% on any and all business being done with the United States of America.
"This order is final and conclusive. Thank you for your attention to this matter!"
