Will Smith refused to let Margot Robbie tattoo him.

The 26-year-old actress showed up on the set of 'Suicide Squad' with a tattoo gun and offered to ink her co-stars, including Will, 47, and Cara Delevingne, 23, but he was not impressed.

He told Entertainment Tonight: ''I'm a grown-ass man. Margot comes bounding into work with all of her 24-year-old glory like, 'Guys! Guys! I got a tattoo gun! I got a tattoo gun! We're all getting tattoos!' I was like, 'No, we're not.'''

And Margot admits her tattoo skills leave a lot to be desired.

She said: ''Picture what a four-year-old would draw and stick it on your fridge. That's kind of one of my tattoos.

''I tattooed Cara's toes and she tattooed mine as well,''

Meanwhile, Will revealed what he loves most about 'Suicide Squad' is that it is a celebration of ''diversity'' because of the eclectic cast and characters.

He said: ''What I love about working with this group, it's a rainbow. It's all races, creeds and colours. It's the diversity that this country is supposed to be about.''

Praising director David Ayer's work on the project, he added: ''I've made a lot of movies, and some of them you can't even count as movies. David Ayer said something that was really interesting: He said it's not a movie of good versus evil, it's a movie of bad versus evil, and this is one of the baddest casts in the whole damn world right here.''

'Suicide Squad' follows the group of incarcerated baddies as they are assembled to form a special black ops team to carry out a highly dangerous mission for a secret US government agency.

The world premiere took place in New York City on Monday (01.08.16) and the Warner Bros. Pictures movie hits cinemas on August 5.