Authorities on the Greek island of Santorini have refused to run anti-donkey ride adverts on local buses and taxis.
The group had intended to place the adverts across the island in time for tourist season.
The adverts follow an exposé by the group, which showed animals being forced to carry heavy loads up the steep Santorini steps.
It also revealed handlers drag animals down the steps and whip and hit them with sticks to make them continue walking.
In addition, when not being made to carry extremely heavy loads on their backs, they're often tethered in the blazing sun without access to water or shade.
GRAPHIC: Footage shows animal suffering
"Greek authorities should be stepping up and stopping donkeys from being marched into the ground in Santorini, not covering up the cruelty of forcing them to carry heavy loads of tourists up hundreds of steps," PETA Director, Elisa Allen, said in a statement sent to Plant Based News.
"PETA is urging people everywhere to tell their travelling friends and family members to refuse to support this abuse and to use Santorini's cable car instead."
The charity adds: "A new law passed this year prevents donkey and mule owners in Santorini from burdening their donkeys with weights exceeding 100 kilograms, even though, according to veterinary recommendations, donkeys shouldn't carry more than 20 percent of their body weight – approximately 50 kilograms."