The US government has asked the 11th Circuit Court of Appeals to reject a request from Delta Air Lines (DL, Atlanta Hartsfield Jackson) and Aeroméxico (AM, México City International) to delay a US Department of Transportation (DOT) order requiring them to unwind their joint venture agreement.

First reported by Reuters, the carriers are seeking to have the January 1, 2026, deadline waived, as ordered by the DOT in September. They argue that doing so would allow the court sufficient time to conduct a review and issue a full opinion.

The DOT ordered the airlines to dissolve their joint venture in response to the Mexican government’s failure to comply with the 2015 US-Mexico Air Transport Agreement. It was the first of several measures the department has taken to address what it perceives as an imbalance in the air transport market between the two countries.

Delta and Aeroméxico have sued the US government in an effort to maintain their joint venture. In their filing, they said that unwinding the venture by January 2026 “would be operationally and financially burdensome.”

The government said the airlines’ claims “of irreparable injury are overblown,” adding that the public interest favours restoring full and fair competition between Delta and Aeroméxico themselves and between them and their competitors.

Other measures include freezing an ATI application from Viva (Mexico) and Allegiant Air, cancelling thirteen new routes from México City International and México City Felipe Angeles, potentially banning belly cargo ops from these two airports to the United States, and imposing further restrictions on scheduled and charter Mexican carriers.

Aeroméxico declined to comment on the story. Delta also declined but added that it had requested a response from the court by November 14.