Actor Shia Labeouf blames "peer pressure" for the tattooed portraits of rapper Missy Elliott on his knees.

The Transformers star reveals he and his American Honey castmates, including Riley Keough and Sasha Lane, bonded off-set with group outings to a tattoo parlor, and he walked away from the upcoming drama with a collection of new skin art.

However, Shia admits he was reluctant to go under the needle for some of the designs, particularly the images of Missy.

"One of the things we'd do as a group, we'd all go to the f**king tattoo shop," he tells Variety magazine.

"I don't love Missy Elliott like I wanna get two Missy Elliott tattoos, but you're in a tattoo parlor, and... peer pressure," he shrugs.