Mexico City - The Delta-Aeromexico transborder joint venture (JV) began offering ultra-low-cost fares March 5 as Aeromexico launched its "branded fares" concept and Delta Air Lines touted the increasing range of basic economy fares on what is now more than 50% of Delta's US-Mexico flights.

Atlanta-based Delta had already offered basic economy fares on flights to Cancun, Puerto Vallarta and Cozumel; the new route expansion includes several new Guadalajara and Mexico City flights, Delta said, adding it expects to have basic economy available on its entire global network by the end of 2018.

Aeromexico said its new fare structure will be available on domestic flights in Mexico, as well as flights to and from the United States and Canada. Aeromexico executives have said the new branded fares structure will appeal to flyers seeking bundled services that Mexican LCC competitors Interjet and Volaris do not offer.

Beyond basic fare, Aeromexico's new fare structure includes five progressively more value-added offerings: classic, flexible, AM Plus, comfort and premier.

Delta and Aeromexico launched a JV in May 2017, which focused on utilizing the hubs of both carriers to provide passengers flying between the US and Mexico with connecting options. Delta has hubs in Atlanta, Detroit, Los Angeles, Minneapolis-St. Paul, New York (both La Guardia and JFK), Salt Lake City and Seattle. Aeromexico has hubs in Mexico City, Monterrey and Guadalajara.

Delta first introduced its basic economy fares - which involves a customer being willing to be seated anywhere on the aircraft, with no flight itinerary changes, no-checked baggage, no adjacent seating for passengers traveling together, among other restrictions - in 2012.

Delta was the first major US airline to introduce the basic economy fare concept. Last October, while discussing the fare option in an analyst's call, Delta president Glen Hauenstein said "the success of that product isn't measured by how many people buy it, but by how many people don't buy it and choose another product."