Josh Gad has insisted Robin Williams' estate gave their consent for his posthumous performance as Genie.

Robin Williams' voice will feature in the short film

Robin Williams' voice will feature in the short film

The 'Frozen' actor will reprise his role as Olaf opposite the late 'Aladdin' star - who took his own life aged 63 in August 2014 - in an upcoming animated short as part of the company’s 100th anniversary celebrations, and the film will feature "previously unheard dialogue" of Williams voicing the beloved character.

Responding to some backlash over the announcement, Gad wrote on Instagram: "It’s important to not jump to conclusions before knowing all the facts. Me getting to act alongside my idol posthumously, using previously unheard dialogue, would NEVER EVER happen without the consent of his estate.

"My love for Robin Williams is literally unmatched and I would never do anything unless I was guaranteed that it was with all of the proper sign-off and support.

"What Disney animation has done with the INCREDIBLE short #OnceUponATimeInAStudio is not only a love letter to my creative hero (and the reason I wanted to play Olaf in the first place), but to a 100 year legacy that is truly unmatched. Please, just enjoy the nice things."

Gad had shared a picture of Genie coming out of an artists' sketchbook and smiling at Olaf, and he admitted he "nearly cried" when he found out the characters were sharing the screen in 'Once Upon A Studio'.

He wrote in the initial announcement: "Now that it’s premiered at Annecy, I’m so excited to finally have the world see what @DisneyAnimation has created to celebrate the incredible 100 year legacy of the studio.

"I nearly cried when I was told Olaf would appear alongside the Genie, utilizing previously unheard audio from my idol #RobinWilliams."

The news was revealed as part of Annecy International Animation Film Festival, with the special animation shown for the first time over the weekend as part of the annual event.

As well as Genie and Olaf, the nine-minute short film features more than 400 other Disney characters, including Mickey and Minnie Mouse, Winnie the Pooh, Moana, Merlin, Tiana, Goofy and more.

As reported by Variety, the project shows the various characters causing "gentle comic mayhem" around the Roy E Disney animation building, with over 40 original voice actors returning for the film.