A woman has been barred from bringing her “emotional-support peacock” on board a US flight.

The passenger reportedly offered to buy the bird its own ticket to board the United Airlines flight to Los Angeles from Newark Airport, according to travel blog Live and Let Fly.

But staff are said to have refused to let the bird – thought to be called Dexter – fly, saying he did not meet the airline’s size and weight guidelines.

Passengers shared their own images of the bird after he was spotted perched on his owner’s shoulder as she walked through the airport.

The peacock is thought to belong to Brooklyn-based artist Ventiko, who adopted him in 2014 for an art project, according to the Bushwick Daily.

A post on the bird’s dedicated Instagram account reads: “Spent 6 hours trying to get on my flight to LA. Tomorrow my human friends are going to drive me cross country! Keep an eye out for us!”

United said the passenger was told in advance she would be unable to bring Dexter on board.

“This animal did not meet guidelines for a number of reasons, including its weight and size. We explained this to the customer on three separate occasions before they arrived at the airport,” a spokesperson said.

“We know that some customers require an emotional support animal to assist them through their journey. In order to ensure we provide the best service to everyone onboard our flights, consistent with government rules we currently require these customers to provide documentation from a medical professional and at least 48 hours advance notice.”

It comes just weeks after Delta airlines announced tougher regulations for passengers bringing emotional support animals on board.

The firm said it had seen a 150 per cent increase in service and support animals – pets, often dogs, meant to support physically disabled passengers or those with emotional or psychiatric problems – carried onboard since 2015.

Alongside that increase has been an 84 per cent spike in the number of reported animal incidents since 2016, including urination and/or defecation, biting, and a high-profile 2017 mauling of a passenger by a 70 pound (32 kg) emotional support dog.

“The rise in serious incidents involving animals in flight leads us to believe that the lack of regulation in both health and training screening for these animals is creating unsafe conditions across US air travel,” said John Laughter, Delta’s senior vice president of corporate safety, security and compliance, in a statement.