Disney accidentally cast a porn star in The Little Mermaid.

Casting bosses working on the live-action remake wanted to use "really sexy male models" to portray the mermen in the film, and among those hired for the job was 24-year-old Stefano Tomadini, who has also made adult movies under the alias Dante Ferrari.

His explicit films, for which he was paid up to £1,000 (S$1,680) a time, are still available to watch online, though viewers have to pay.

A source told The Sun newspaper: "Casting bosses decided to hire a number of really sexy male models to play mermen in the movie.

"They had no idea about Stefano's racy videos and, given The Little Mermaid is the big summer blockbuster for kids, it's a bit embarrassing for Disney."

While filming the movie in Sardinia, Stefano shared a number of behind-the-scenes photos on Instagram.

Tagging Disney in the post, he wrote in the caption: "Lifetime memories with lifetime friends."

A spokesperson for Disney declined to comment.

The Rob Marshall-helmed remake — which stars Halle Bailey in the title role — was previously dubbed "a classic" by big wigs at the movie studio and seen as an obvious choice for a reimagining.

Tony Chambers, the head of distribution at Disney told Variety: "It's a classic. You ask a lot of women or men of my age and it's The Little Mermaid and Beauty and the Beast that rank as their favourite animated movie.

"It's a story that takes them back to their respective childhoods and this movie is the perfect opportunity for a lot of people to pass that love on to the next generation."