Donald Trump has slapped any country doing business with Iran with a hefty tariff in response to the Islamic Republic's deadly crackdown on anti-government protests – even though the US itself has a small amount of trade with the country.
The US president announced this morning (AEDT) that Iran's business partners will face a 25 per cent duty in the United States.
"Effective immediately, any Country doing business with the Islamic Republic of Iran will pay a Tariff of 25 per cent on any and all business being done with the United States of America," he wrote on social media.
READ MORE: Young fashion student shot in back of head during Iran protests: watchdog
"This Order is final and conclusive. Thank you for your attention to this matter!"
Iran is already subject to a wide range of international sanctions, but has major trade arrangements with several other countries, including China, Russia, Brazil and the United Arab Emirates.
It does, however, also trade in much smaller volumes with Western nations, including Germany, Italy, and Australia.
According to the Department of Foreign Affairs and Trade, there was about $730 million in trade between Australia and Iran in 2024.
Even the United States itself does a small amount of trade with the Islamic Republic.
According to the US Census Bureau, there was slightly less than $US50 million worth of goods traded between the two countries (roughly $73 million) in the 10 months to October 2025.
In his social media post, Trump did not detail how exactly the new tariffs will work.
Trump had previously said Iran wanted to negotiate with Washington in regard to the protests, which have escalated into nationwide demonstrations over the past three weeks, having started at two markets in Tehran in response to the plummeting local currency.
READ MORE: Trump says Iran wants to negotiate as death toll rises to at least 572
According to the US-based Human Rights Activists News Agency, almost 600 people have been killed in the protests, and more than 10,000 detained, although some estimates have put the death toll in the thousands.
The president has also threatened military action against Iran, and has been weighing options including cyberattacks and direct strikes by the US or Israel.
"The military is looking at it, and we're looking at some very strong options," Trump told reporters on Air Force One.
Asked about Iran's threats of retaliation, he said: "If they do that, we will hit them at levels that they've never been hit before."
– with Associated Press
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