Ariana Grande has insisted singing live in 'Wicked' was a "no-brainer".

The 31-year-old actress stars as Glinda alongside Cynthia Erivo as Elphaba in the upcoming big screen adaptation of the iconic Broadway musical, and they were determined to sing live on set rather than dub their vocals in post-production.

She told E! News: "It was an immediate no brainer for Cynthia and I. We both were like, 'Well of course we're singing live.' "

Her co-star, 37, agreed and insisted there is "something special" about performing and filming in that way.

She added: "There's something special about what happens when music is live in a room."

'The Boy Is Mine' hitmaker Ariana threw everything into her character, and even worked on changing the natural pitch of her speaking and singing voice.

She recently told the New York Times newspaper: "It was really important to erase as much of myself as possible, so that they could just be looking at Glinda.”

She has been met with backlash from trolls online after traces of Glinda's high octave have remained in her voice for months after filming wrapped.

However, she previously told Vanity Fair: "There is a part of the world that isn’t familiar with what it takes to transform your voice, whether it’s singing or taking on a different dialect for a role or doing a character voice for something.

"When it’s a male actor that does it, it’s acclaimed.

"There are definitely jokes that are made as well, but it’s always after being led with praise: ‘Oh, wow, he was so lost in the role.’ And that’s just a part of the job, really.”

Despite the critics, Ariana is "really proud" of the work she's done and the voice she figured out for Glinda.

She explained: "Part of why I did want to engage [with critics] is because I am really proud of my hard work and of the fact that I did give 100 percent of myself, including my physicality, to this role. I am proud of that, so I wanted to protect it.”