It's about to get a lot more difficult to fly with an emotional support animal on Delta Air Lines.
Delta announced Friday that beginning March 1st, all passengers bringing animals into the cabin will be required to provide documentation from a doctor or mental health professional.
They will also need a signed letter stating the animal is trained to behave without a kennel.
The airline says the decision was made after repeated incidents involving untrained animals biting passengers and relieving themselves on airplanes.
Delta also says customers have tried to pass off animals including turkeys, sugar gliders, snakes and spiders as comfort pets.
It will no longer accept any exotic or unusual service animals.
According the airline, about 700 service animals fly on its planes each day.