WASHINGTON -- The United States has imposed sanctions on all of Iran's remaining active airlines, sharply escalating pressure on Tehran's aviation sector as part of a broader campaign aimed at cutting the Islamic republic off from international trade and finance.The US Treasury Department on September 8 sanctioned 36 targets, including 27 Iranian airlines, as well as foreign companies and an individual accused of helping Iran's sanctioned aviation networks procure aircraft, aircraft parts, and other technology.The action marks the first time Washington has used a new August 24 determination targeting Iran's aviation sector to sanction the country's remaining airlines. Treasury said the sector is used by the Iranian government to move weapons, personnel, and illicit cargo."Let this be a warning to anyone doing business with Iran's remaining airlines, all of which we sanctioned today: You are at risk of being cut off from the global financial system," Treasury Secretary Scott Bessent said."We will not relent in our campaign to shut down the Iranian regime's financial lifelines, including the aviation sector," State Department spokesman Tommy Pigott said in a statement.

The sanctions come under President Donald Trump's so-called Operation Economic Outcast, announced by Bessent on August 24 as part of a campaign to sever what Washington describes as the Iranian regime's remaining economic lifelines.Among the airlines designated are Iran Aseman Airlines, Iran Airtour, Kish Airlines, Qeshm Air, Karun Airlines, Sepehran Airlines, Taban Airlines, Varesh Airlines, Zagros Airlines, Chabahar Airlines, Fly Persia, and Saha Airlines, formally known as the Armed Forces Air Transport Service.Other carriers sanctioned include Air Shiraz, Ava Airlines, Fly Kish, Mehr Airways, Raimon Airways, and Soroush Air.There was no immediate public response from Iran to the September 8 measures.Targeting Iran's Aviation LifelinesThe Treasury action goes beyond Iranian carriers, targeting a network of foreign companies that Washington says helped sanctioned Mahan Air acquire aircraft and operate international flights.Mahan Air has been under US counterterrorism sanctions since 2011. Washington accuses the carrier of providing logistical support to Iran's Islamic Revolutionary Guards Corps (IRGC), including by transporting personnel, weapons, and military equipment.The Treasury said Mahan Air received at least three Boeing 777 aircraft this summer through a route involving the United Arab Emirates and Oman. The UAE-based ECT Aviation Support and Turkey-based Sky Phoenix were identified as intermediaries in what Washington described as a scheme to transfer US-origin aircraft to Mahan Air.ECT Aviation Support's owner and chief executive, Egyptian national Mahran Ibrahim Ali Mohamed Mahran, was also sanctioned.