Washington, United States: US Treasury Secretary Scott Bessent has warned that all Iranian airlines will be shut down worldwide from 23 September, 2026 as the US expands secondary sanctions against foreign companies providing essential services to Iranian carriers. Bessent said the measure would target not only Iranian airlines but also airports, fuel suppliers, landing-service providers and ticketing companies that continue supporting them.
Speaking to CNBC on 21 September 2026, Bessent said, “On September 23, all the Iranian airlines will be shut down around the world.” He explained the mechanism by saying, “If they land, you cannot provide them with fuel, you cannot provide them with landing services, you cannot sell them tickets, or you will be knocked out of the dollar system.”
The warning represents a major escalation in the US campaign to isolate Iran economically. The latest pressure follows the US Treasury’s 8 September sanctions action against Iran’s aviation sector, which targeted 36 individuals and entities and included 27 Iranian airlines that had not previously been sanctioned. The US has accused parts of Iran’s aviation network of supporting the movement of weapons, personnel and other cargo.
The latest threat is designed to extend the impact of sanctions beyond Iranian airlines themselves. Instead of relying only on restrictions against the carriers, the US is warning foreign companies that continue to provide the services required for international flights that they could lose access to the US dollar financial system.
The warning covers services including aircraft refuelling, landing arrangements, ground handling and ticket sales. This is significant because an airline can hold an aircraft and crew but cannot sustain an international route without airport access, fuel, ground support and passenger-ticketing arrangements.
Bessent also linked the latest action to Washington’s wider economic campaign against Tehran. His comments came after talks with Chinese Vice Premier He Lifeng. Bessent said Chinese officials had been “very engaged” in the US pressure campaign and said Washington was having positive discussions with Chinese financial authorities, including People’s Bank of China Governor Pan Gongsheng, over compliance with US sanctions on Iran.
The threat comes as Iranian international connectivity is already shrinking. Mahan Air suspended flights between Iran and Turkey from 21 September, including services between Tehran and Istanbul and Tehran and Ankara. The airline also suspended its services to Georgia from 21 September. Mahan Air had already suspended its Tehran-Muscat route from 17 September following a decision by Omani aviation authorities. Mahan said the restrictions followed decisions by the relevant aviation authorities and did not amount to a closure of Iranian airspace.
Georgia also suspended flights operated by Iranian airlines affected by US sanctions from 21 September. The last such flights operated on 20 September. Georgia’s Civil Aviation Agency had earlier said it would act in “full compliance with the international sanctions regime”, including the sanctions imposed by the US and European Union.
Turkey has separately stopped flights by Turkish Airlines to Iran until at least March 2027. A Turkish Airlines representative told Iran International that the carrier had no flights scheduled to Iran before March and that there was no guarantee services would resume at that time.
Reports on 21 September also said AJet and Pegasus had removed or suspended Iran services, further reducing direct connectivity between Turkey and Iran.
Iraq became another major point of disruption on 21 September. One Iraqi official said, “Iraq will enforce the ban on Iranian airlines in accordance with the US Treasury decision starting Tuesday at dawn,” and warned that “countries that do not implement the decision risk sanctions.” An Iraqi government source confirmed the decision.
The decision is particularly significant because Iraq is a major destination for Iranian travellers, including passengers travelling to Najaf and Karbala for religious purposes.
However, there was an important development from Iran Air on the same day. Iran’s national carrier said it would continue operating flights from Tehran, Mashhad and Isfahan to Najaf according to its scheduled timetable. The announcement came despite Iraqi sources saying Iranian airline operations would be suspended from Tuesday and despite Bessent’s warning of a global shutdown from 23 September.
This means that, as of 21 September, the situation was not yet a complete worldwide grounding of every Iranian flight. Some routes had already been suspended, some governments had announced restrictions, while at least Iran Air was still publicly saying its Najaf services would continue.
Foreign airlines have also reduced or suspended services to Iran independently of the new 23 September deadline.
Turkish Airlines said its Iran flights were suspended until at least March 2027. Emirates said it was no longer operating flights to Tehran, while Lufthansa and Austrian Airlines said their Iran services were suspended until at least 24 October 2026. Qatar Airways said its Iran services were currently suspended because of airspace restrictions, with a tentative 29 November restart date that could change depending on conditions.
Iran International also reported that travel agencies were unable to book some services involving airlines from Russia, China and Oman, as well as Pegasus Airlines and carriers operating routes from Armenia. These booking conditions could change at short notice and did not necessarily represent formal permanent cancellations.
The 23 September deadline announced by Bessent does not itself establish that every Iranian aircraft will physically be prevented from entering every foreign airspace. Instead, the US is seeking to make international operations commercially and financially difficult by threatening companies that provide the services required to operate those flights.
The practical impact therefore depends on how airports, fuel suppliers, ground handlers, ticketing companies, financial institutions and national aviation authorities respond.
Iranian airlines were already operating under severe restrictions caused by years of sanctions, which have limited access to aircraft, spare parts and maintenance support. The new measures add pressure at the operational level by targeting the foreign infrastructure on which international flights depend.
The next major deadline is 23 September, when the US says secondary sanctions will be used against foreign entities that continue providing services to Iranian airlines.
