Treasury official Jonathan Burke, a former banker, made a secretive trip across the Middle East and Europe warning governments they must choose between trading with Iran and keeping their ties with Washington, in a campaign that has contacted more than 50 countries, the Wall Street Journal reported. The pressure has already produced flight bans by Oman, the UAE, Iraq and Turkey, along with banking restrictions.

The push follows Treasury Secretary Scott Bessent's September 23 deadline to shut down all Iranian airlines worldwide. "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," Bessent said. Treasury sanctioned 27 Iranian airlines on September 8, a step it said covered all of the country's remaining carriers. Turkish Airlines, Pegasus and AJet canceled all Iran flights from September 21, with no bookings available until at least March 2027, and the UAE, Iraq, Oman, Georgia and Azerbaijan have suspended Iranian carriers.

Iran says flights to Turkey, China, Malaysia, Vietnam, Afghanistan and Pakistan continue, with no new cancellations beyond earlier restrictions on routes to the UAE, Iraq, Oman, Georgia and Saudi Arabia. China, Iran's largest remaining aviation market, said it will keep allowing Iranian airlines to operate on its territory, and a Mahan Air aircraft landed in Guangzhou hours after the US order took effect. Iran's Supreme National Security Council secretary, Mohsen Rezaei, warned neighboring countries against complying. "If you side with America, we will not just watch," Rezaei said. "Your airports will have no flights."