Trump threatens Iran’s partners: How do secondary sanctions work?

The United States has announced a slew of caller economical sanctions against Iran and threatened countries it trades with, aiming to choke Tehran’s system arsenic the months-long struggle remains deadlocked.

At slightest 60 entities crossed the Middle East, Asia and Europe person been targeted successful the latest sanctions arsenic portion of the economical unit run that could further disrupt vigor markets and rattle the planetary economy.

The US-Israel warfare launched connected February 28 has already resulted successful a spike successful lipid prices and disruption successful planetary proviso chains owed to the blockade of the Strait of Hormuz, done which a 5th of planetary lipid and state antecedently passed.

In this explainer, we interruption down however secondary sanctions work, and erstwhile the US has utilized them successful the past.

What has the US threatened Iran’s trading partners with?

The Trump medication has already been waging an economical unit run against Iran nether the banner of “Operation Economic Fury”, since the motorboat of the warfare successful February.

However, the US has precocious decided to up the ante with “Operation Economic Outcast”, targeting countries that commercialized with Iran arsenic well.

US Treasury Secretary Scott Bessent said connected Monday that the US would people each of Iran’s sources of revenue, including oil, to forestall different countries and companies from doing concern with Tehran.

“Around the globe, our nonsubjective is to sever each economical lifeline that sustains this tyrannical authorities until Tehran stands alone,” helium said.

He said countries astir the satellite indispensable take betwixt the US and Iran, stressing that the caller run exposes Tehran’s commercialized partners to secondary penalties.

Bessent added that if countries and entities “facilitate transactions and are portion of the ecosystem that turns Iranian lipid into money, into repression, they volition beryllium targeted”, helium said.

Asked wherefore the US is threatening Iran’s concern partners alternatively of penalising them, Bessent said: “Well, we are giving everyone the accidental to remedy atrocious behaviour. Why would I privation to stroke up the planetary fiscal system?”

Bessent’s latest statements are a follow-up to US President Donald Trump’s Truth Social station connected August 19, wherever the president announced what helium called the “most crushing economical operation” against Iran.

“ANY state that allows its fiscal institutions, businesses, airports, oregon authorities entities to supply immoderate benignant of lifeline to Iran volition itself look TREMENDOUS Economic Consequences,” Trump wrote.

What are secondary sanctions?

The US has agelong utilized threats of what are known arsenic secondary sanctions – successful which countries that commercialized with a sanctioned state besides look sanctions.

For instance, secondary sanctions are successful spot against the acquisition of Iranian lipid oregon dense subject instrumentality from Russia: countries, companies and individuals that prosecute successful this commercialized are astatine hazard of US sanctions.

How bash they work?

The US’s main leverage is entree to its marketplace and fiscal system.

For instance, adjacent if an Indian slope has nary nonstop narration with Iran, it could look secondary sanctions if it processes payments for an Indian steadfast trading with Tehran, particularly if that slope has US branches, dollar‑clearing ties oregon American clients.

That hazard makes institutions hyper‑cautious, avoiding thing that adjacent touches Iran for fearfulness of being swept up successful US penalties.

The menace of secondary US sanctions is besides wherefore astir planetary banks and fiscal institutions nary longer enactment successful commercialized with Russia oregon Iran – they bash not privation to hazard losing concern successful the US.

How person secondary sanctions been utilized successful the past?

In 2017, Trump’s archetypal medication authorised the Countering America’s Adversaries Through Sanctions Act (CAATSA), targeting Iran, Russia and North Korea.

Under CAATSA, the US targeted circumstantial countries with secondary sanctions. In 2018, it targeted the Equipment Development Department (EDD) of the Chinese subject owed to its purchases of Russian Su-35 combatant jets and S-400 rocket systems.

In 2020, Washington utilized the CAATSA sanctions to target NATO-member Turkiye’s Presidency of Defence Industries, the country’s subject procurement agency, alongside immoderate officials affiliated with it. This came a twelvemonth aft the US barred Turkiye from procuring US F-35 combatant jets.

Turkiye was earmarked for its acquisition of the Russian S-400 aerial defence strategy successful 2019. Trump’s calculus was that the S-400s were incompatible with NATO instrumentality and a perchance threatened allied security.

These sanctions made Turkiye cautious astir making aboriginal purchases. In July 2026, Trump said helium would lift sanctions connected Turkiye and would soon determine connected resuming income of F-35s.

Any determination to instrumentality Turkiye to the F-35 programme would request to flooded a 2020 instrumentality requiring a statesmanlike medication to find that Ankara nary longer possesses oregon operates the Russian systems.

While the CAATSA sanctions were highly targeted, it is unclear whether immoderate sanctions imposed connected Iran’s trading partners would be.

Who are Iran’s main trading partners?

In 2024, Iran exported immoderate $56bn worthy of goods to astatine slightest 112 countries and territories, according to authoritative customs figures. In the aforesaid year, Iran imported astir $68.5bn worthy of goods from astatine slightest 87 countries and territories.

Its apical export partners were China, Iraq, the United Arab Emirates, Turkiye and Afghanistan. Its apical import partners were the UAE, China, Turkiye, the European Union and India.

Washington’s leverage implicit Iran’s trading partners is contingent connected the trading partners’ reliance connected the American fiscal system. For respective sectors successful China and Russia, this reliance is minimal. Hence, analysts accidental that Trump’s leverage implicit China and Russia is limited.

Those sectors see astir of China’s lipid refineries. According to analytics steadfast Kpler, China bought 80 percent of Iran’s shipped lipid successful 2025.

Paul Musgrave, an subordinate prof of authorities astatine Georgetown University successful Qatar, told Al Jazeera past week that “it is going to beryllium precise difficult” for Trump to propulsion disconnected his unit run effectively.

Analysts accidental China could besides deed backmost if the US sanctions its banks for processing Iranian funds, arsenic the US Treasury has threatened.