When it comes to cola, most people tend to fall into one of two camps: Coke or Pepsi.

And by the looks of things, most of JetBlue’s customers are Coca-Cola lovers.

The airline announced it would be switching the Coca-Cola served on board for Pepsi – and customers weren’t happy.

“We’re refreshing our core complimentary beverage line-up to offer customers exciting new product options they’ve asked for, while also bringing sustainability benefits, and controlling growing costs,” an internal JetBlue communication seen by USA Today read.

"Most notably, this includes the introduction of Pepsi products to our offering beginning June 3."

A spokesperson for the budget airline confirmed the news to INSIDER, saying: "JetBlue is always looking for ways to refresh our onboard experience.

"Starting June 3, we will offer a new selection of complimentary beverages on all JetBlue flights. Additional details will be shared in the coming weeks."

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Coca-Cola fans have been expressing their dismay at the change on social media.

"Please please don't switch to Pepsi. Coke is the real brand, while Pepsi is like hot garbage juice after morning pickup," wrote one person on Twitter.

Another traveller revealed she was "devastated."

"Pepsi? What are we monsters? Bring back the Coke," implored a further Coca-Cola lover.

"We want Coke!" agreed another.

However, some Pepsi preferrers have been expressing their joy at the news.

American singer Clay Aiken, for example, is thrilled.

https://twitter.com/clayaiken/status/1129876987944800262?ref_src=twsrc%5Etfw

"Now they are offering better products," added another fan.

One traveller implied the soda brand change might even make her specifically choose to travel with the airline.

Further changes to the JetBlue on-board service include pouring water from larger bottles, and the serving of snacks and drinks at the same time on short-haul flights.

This isn't the first time an airline has caused a stir by changing its in-flight menu - earlier this month, British Airways was widely ridiculed for the introduction of "afternoon tea" on board, which, curiously, did not include any tea.

INSIDER has contacted PepsiCo, and Coca-Cola for comment.