On Saturday, July 19, US Secretary of Transportation Sean P. Duffy announced a series of "America First" actions against Mexico, which he believes is engaging in anti-competitive behavior and violating the 2015 bilateral air transport agreement between the United States and Mexico, effective 2022. Three years ago, Mexico revoked slots (time slots for flight operations) from three US carriers (American, Delta, United) and three Mexican ones (Aeromexico, Viva Aerobus, Volaris), operating scheduled passenger flights at Mexico City's "Benito Juárez" international airport (Mex), allegedly due to construction work to alleviate congestion at the airport, which has not yet been completed. In 2023, Mexico also unilaterally forced all US cargo carriers to leave the country, citing capacity congestion and giving only 108 business days' notice.

According to a statement from the US Department of transportation (DoT), "by limiting slots and forcing cargo operations out of Mexico, Mexico has broken its promise, disrupted the market, and left American companies holding millions of dollars in additional costs". Therefore, the US plans three "America First" actions against Mexico: "requiring Mexican airlines to submit to the Department the schedules of all their US operations"; "requiring prior Dot approval before operating charter flights for passengers or large cargo to or from the United States"; and "revoking the Antitrust Immunity (ATI) of the Delta/Aeromexico joint-venture, thereby taking corrective measures to address competition concerns in the market".

The DoT is also examining which other countries are ignoring the terms of air transport agreements: in particular, it is monitoring European states to ensure that they are correctly applying the balanced approach to noise reduction at their airports and that they are not applying unjustified operating restrictions.

"America First" is a term used to describe a US foreign policy aimed at prioritizing American national interests over those of other countries, often with an isolationist or protectionist approach. In practice, this translates into less participation in international alliances, a greater emphasis on domestic production, and a US-centric worldview.