London: A giant rabbit almost a metre long has died on a United Airlines flight from London, weeks after the airline faced a global backlash over its treatment of a passenger who was dragged from his seat.

The 10-month old rabbit named Simon, who was tipped to become one of the world's largest rabbits, was travelling to O'Hare International Airport in Chicago from Britain after a celebrity owner bought him.

He was healthy before the flight, the rabbit's breeder said.

"Simon had a vet's check-up three hours before the flight and was fit as a fiddle," breeder Annette Edwards told The Sun newspaper.