Washington, Dec 3 (IANS): Under a new regulation issued by the US Department of Transportation, airlines will no longer consider emotional support animals as service animals, limiting dogs as the only type that can fly with travellers for free.

In a revision to its Air Carrier Access Act, the Department said on Wednesday that it"defines a service animal as a dog, regardless of breed or type, that is individually trained to do work or perform tasks for the benefit of a qualified individual with a disability", reports Xinhua news agency.

According to the Department, the revision is partly due to "disruptions caused by requests to transport unusual species of animals onboard aircraft" and increasing incidents of travellers "fraudulently representing their pets as service animals" to avoid charges for transporting pets.

Most service animals are dogs, while passengers are growingly taking various animals onboard for "emotional support", including cats, pigs, miniature horses, hamsters, and even peacocks.

With the new rule, airlines are allowed to recognize emotional support animals as pets, rather than service animals.