VivaAerobus (VB, Monterrey Mariano Escobedo) and Allegiant Air (G4, Las Vegas Harry Reid) hope the US Department of Transportation (DOT) will reinstitute its procedural schedule for its review of their Antitrust Immunity (ATI) application if it decides to withdraw its impending termination of Delta Air Lines' and Aeroméxico’s joint cooperation agreement's (JCA) existing ATI.

The DOT paused its review of Viva and Allegiant’s application on August 2023 saying it had concerns about how the Mexican government has implemented the US-Mexico air services agreement. In January, it tentatively dismissed Aeromexico and Delta’s application to renew their ATI for the same reasons. In particular, the Department was worried about the Mexican government’s actions, including the forced relocation of all cargo flights out of México City International to México City Felipe Angeles, and three consecutive capacity reductions at MEX.

In February 2024, Delta-Aeromexico and VivaAerobus-Allegiant submitted their own respective objections to the DOT’s decision to terminate the Skyteam members' ATI in separate filings.

“The issues cited by DOT regarding circumstances at a single airport, Benito Juárez International (MEX), do not call into question in any material way the actual access enjoyed by US airlines to Mexico or the prospects for the impactful new entry that Allegiant and Viva seek to introduce,” the two ultra-low-cost airlines argued.

They added that any differences over the measures taken by Mexican authorities should be addressed and resolved through diplomacy and the dispute resolution mechanisms available to the DOT.

Moreover, VivaAerobus and Allegiant would object if the DOT established a “holding pattern” in both cases because it would allow the Delta-Aeromexico alliance to continue operating indefinitely while blocking their partnership.

The two ULCCs proposed a 15-year Joint Venture in late 2021, which would “dramatically expand” nonstop leisure routes between both countries and a USD50 million equity investment from Allegiant Air in VivaAerobus. They identified over 250 new potential route opportunities, with 92 new partnership routes launched within the first two years.

The ch-aviation fleets module shows that VivaAerobus’s fleet comprises 81 in-house aircraft, including twenty-three A320-200s, twenty-two A320-200N, ten A321-200s, and twenty-six A321-200NX. Additionally, it wet-leases fourteen A320-200s from Avion Express Malta (4X, Malta International) due to ongoing Pratt & Whitney engine issues.

Allegiant Air’s fleet comprises 130 aircraft, including thirty-five A319-100s and ninety-five A320-200s.