US Treasury is threatening sanctions on firms servicing Iran’s sanctioned carriers

Washington is squeezing Iran’s airlines through the ground network that keeps them flying: Companies and airports that keep servicing sanctioned Iranian carriers after today risk US penalties, US Treasury Secretary Scott Bessent told CNBC — including potentially losing access to the greenback system. The warning follows the Treasury’s sanctioning of Iran’s 27 remaining active airlines earlier this month, part of its Operation Economic Outcast campaign.

Sanctions don’t need to touch a single plane: Refueling, landing, parking services, ticket sales, and ground handling could all become sanctions chokepoints, Richard Maslen, head of analysis at Capa — Center for Aviation, tells EnterpriseAM. Iranian carriers may be able to work around one disrupted service, but replacing an entire chain of suppliers is much harder, he adds. US sanctions only become an operational constraint when foreign handlers, fuel suppliers, and banks refuse to work with Iranian carriers, Maslen adds.

Here’s where the exposure sits: The airports most exposed include Najaf, Istanbul, Baghdad, Dubai, New Delhi, Shanghai, Guangzhou, Shenzhen, and Phuket, Al Jazeera reports. Privately owned Mahan Air still services China, India, Iraq, Pakistan, Thailand, and the UAE, while Qeshm Air flies to Turkey, Iraq, the UAE, and Germany.

Iraq has now ordered the suspension: Iraq's civil aviation authority has told airlines to halt Iranian flights into Baghdad airport starting tonight at midnight, two sources told Reuters. Baghdad is also weighing diverting Iran Air flights to Najaf airport instead, according to two sources familiar with the matter.

Tehran is responding in kind: Iran's Civil Aviation Organization (CAO) has canceled flights between Tehran and both Baghdad and Muscat from today, while Istanbul and its other international routes continue on schedule, state news agency Tasnim reports. A CAO spokesperson told news agency ISNA that Iranian travelers currently aren't being admitted at Oman's airport, with talks over the issue ongoing.

Iran doesn't need a large network to stay internationally connected — just a reliable core, Maslen argues, built around the handful of countries still willing to serve it. That would leave a smaller, more concentrated network, but he doubts one of that size could sustain an airline rather than simply keep a few routes alive.

“The lost traffic matters, but the precedent could matter much more,” Maslen says. Iraq matters to Iranian carriers in its own right, but the bigger risk is that other airports and suppliers quietly decide the exposure isn't worth it — shrinking the network, route by route, without a single government issuing a formal ban, he notes.

What to watch next: “Watch the aircraft before you watch the headlines,” Maslen says. Falling utilization, more grounded planes, and route suspensions will show whether sanctions are biting before fuel, handling, ticketing, and payment problems even surface. Mahan Air's recent suspension of several international routes is an early sign of how fast that pressure can turn into network losses, he notes.