Measures affecting Iranian airlines took effect on September 23, leading to numerous cancellations of international flights, including those to the United Arab Emirates. Tehran claims to have filed a case with the International Court of Justice to challenge these measures. Iran also claims to have submitted an official protest to the International Civil Aviation Organization (ICAO) regarding sanctions imposed by Washington on its airlines. The head of the Iranian Civil Aviation Organization, Abouzar Shiroudi, announced on September 28 the submission to ICAO of a protest accompanied by documents describing the disruptions in traffic. "To defend the legitimate rights of the aviation sector and counter the illegal restrictions imposed by the United States, Iran has drafted and submitted an official protest to ICAO," he said, according to the official agency IRNA. This characterization of "illegal" is that of Iranian authorities, not a conclusion from the international organization. On September 8, the U.S. Treasury announced measures targeting 36 entities linked to Iranian aviation, including 27 airlines. Iran Airtour, Iran Aseman Airlines, Qeshm Air, Kish Airlines, and Zagros Airlines are among the carriers newly added to the U.S. list; Mahan Air was already under sanctions. Washington accuses actors in the sector of facilitating the transport of equipment and personnel for the Iranian regime, as well as the acquisition of American-made planes and technologies. These are the reasons given by the U.S. Treasury, contested by Tehran. The most visible disruption concerns the United Arab Emirates, which have suspended flights by Iranian airlines to and from their territory. The disappearance of Dubai from the schedules of these carriers deprives their passengers of an important stopover to Europe, Asia, and Africa. Turkey remains a transit hub, but the situation varies by airline: Mahan Air has suspended its flights to this country at the request of Turkish authorities, while Iran Air continued daily flights to Istanbul. Flights to China, Russia, and Pakistan also remained in place. On the Iraqi side, Baghdad sought an exemption to preserve, in particular, pilgrim, student, and patient travel. The extent of the traffic decline is also subject to divergent figures. According to a count by Flightradar24, 41 flights took off or landed at the Imam-Khomeini International Airport in Tehran on Sunday, September 27, compared to about 80 to 90 daily flights the two days before the expiration of U.S. authorizations. The airport management, however, stated 60 flights on that Sunday and claimed that more than 30 international destinations remained served.