What countries do business with Iran and what could new US tariffs mean?

US President Donald Trump said that countries doing business with Iran will face a 25 percent customs duty on their trade with America.

This comes as Iran cracks down on anti-government protests, with thousands feared dead.

This is 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 25% tariff on all business with the United States.

“This order is final and conclusive. Thank you for your attention to this matter!”

The president did not go into any detail beyond that.

Of more than 100 countries that trade with Iran, China is Iran’s largest export partner.

It has purchased more than $14bn (£10.4bn) of products from Iran by October 2025, according to Trade Data Monitor figures.

China is followed by Iraq, which bought goods worth $10.5 billion from its neighbor. Iran also counts the United Arab Emirates and Türkiye among its biggest customers.

In fact, exports from Iran to Türkiye showed a huge jump from 4.7 billion dollars in 2024 to 7.3 billion dollars last year.

Almost all of Iran’s top 10 exports are fuel-related; Iran is one of the world’s largest oil producers.

It also sends foods such as peanuts and tomatoes to other countries. However, it is a much larger buyer of basic materials than its trading partners.

Approximately one-third of Iran’s imports constitute food, including corn, rice, sunflower seeds and oils, as well as soybeans.

However, Iran’s biggest import is gold.

It imported $6.7 billion worth of gold in the 12 months to October, compared with $4.8 billion the previous year.

Trump’s post states that the 25% tariff “will go into effect immediately” and that the order is “final and conclusive.”

However, there is no statement yet from the White House about how this application will work in practice or specifically to which countries it will be applied.

We don’t know whether this will include all countries doing business with Iran or just its largest trading partners.

It’s also unclear whether the 25 percent tax would come on top of existing tariffs that the Trump administration has already implemented.

The USA also did not specify under which law the new tariff would be applied. The comprehensive tariffs announced last April were implemented under the International Emergency Economic Powers Act.

But that is currently subject to a legal challenge at the U.S. Supreme Court, which will be decided on Wednesday. on Monday Trump says USA will be ‘ruined’ if these tariffs are not complied with.

It may be difficult to implement the recommended tariff. Iran is estimated to earn $78 billion from oil exports in 2024 by using a fleet of shadow ships that are difficult to track and selling its oil in Chinese yuan rather than the more traditional US dollar.

On the face of it, Trump’s announcement risks reigniting the trade dispute between the US and China.

If the president means what he writes, that means Chinese goods shipped to the United States should immediately be subject to a new 25% tariff.

But they are already subject to an average tariff rate of 30.8%, according to Bloomberg Economics.

So, will a new tariff be applied in addition to the existing tax? Or will an allowance be given?

China has previously shown a willingness to push back against what it perceives as disproportionate action by the United States.

It did this partly by imposing its own tariffs, but more importantly by imposing restrictions on the export of rare earths that the United States desperately needed for its tech-heavy industries.

China now dominates global supply, giving it significant leverage, which helped Beijing reach a temporary trade truce with the United States in November that eased tensions.

So imposing a new 25% tariff on China now would be extremely provocative, and Beijing has already warned that it will “take all necessary measures to protect its legitimate rights and interests.”

Analysts question whether this will actually happen, given that the real-world impact of previous Trump announcements has not always matched the initial headline.

Iran’s huge oil reserves make it one of the world’s top 10 oil producers and should be a source of great wealth.

But its economy has been paralyzed by years of mismanagement of public finances, a decline in oil sales and the tightening of international sanctions.

Many of the country’s 92 million people struggle to meet basic needs such as food and utilities, and the cost of living has been at the center of protests seen in recent weeks.

Household spending has fallen from its peak in 2008 and government restrictions on women being able to work have reduced the employment rate to around 37%, from 42.4% two decades ago, according to BBC analysis.

At the same time, things have become more expensive thanks to high inflation, which reached 48.4% in October amid government policy changes that sent the value of the rial falling against the US dollar.

This makes imports even more expensive. These are all the more important because significant underinvestment in electricity and water systems means these systems are unreliable and undermines government commitments to increase domestic production of everything from food to consumer goods.

The reduction of fuel subsidies in December and potentially even less foreign trade due to these latest tariffs means inflation could rise further, pushing the economy even closer to collapse.

Additional reporting by Theo Leggett and Jonathan Josephs.