Lady Gaga has compared Dr. Luke to a Disney villain.
The 30-year-old singer is horrified that Kesha - who claims the producer sexually abused her for years - has been banned from performing at the Billboard Music Awards on May 22 after his label Kemosabe records "rescinded its approval" following concerns she'd speak out about their ongoing legal battle.
Comparing Luke to 'The Little Mermaid's villainess Ursula, who steals Ariel's voice, she tweeted: "Listen Ursula, we want her voice back. #freeKesha (sic)."
Gaga - who has been one of Kesha's most vocal supporters in her battle to be released from her contract by Luke's label - also tweeted a link to a story about the controversy and wrote: "Isn't it strange that it's legal to own a woman this way?"
After it was reported that Kesha was planning a statement performance in which she would make "direct references" to her battle with Luke - who has denied all allegations against him - Kemosabe records banned her from taking to the stage.
A representative for Billboard Awards producer Dick Clark Productions said: "Kesha accepted an invitation to perform on the show and she received written approval from Dr. Luke's record label, Kemosabe Records. Kemosabe subsequently rescinded its approval following a media report on Wednesday, May 11th regarding Kesha's appearance on the BBMAs.
"Unfortunately, Kesha and Kemosabe have since been unable to come to an agreement for Kesha to perform on the show. Dick Clark productions has a long standing relationship with Kesha. We hope that the parties can come to an arrangement such that we can continue that long standing relationship with a performance by Kesha on the Billboard Music Awards stage on May 22nd."
However, the 29-year-old singer is adamant she had no intention of bringing up the long-running court case and was merely interested in sharing her love of music.
She wrote on Instagram: "I was very excited to perform a tribute to Bob Dylan by singing a cover of 'It ain't me, babe' at the Billboard awards this year. I'm very sad and sorry to say I won't be allowed to do this.
"I just wanted to make very clear that this performance was about me honoring one of my favorite songwriters of all time and has never had anything at all to do with Dr. Luke.
"I was never going to use a picture of him, speak of him or allude to my legal situation in any way. I simply wanted to sing a song I love to honor an artist I have always looked up to. thank u all for the continued support. (sic)"
And Kesha's mother, Pebe Sebert, has urged music stars to get behind her daughter by refusing to perform at the event.
She tweeted: "Wouldn't it be nice if other artists stood with Kesha and refused to preform if she is not allowed to sing!
"Are KEMOSABE's actions today the actions of a record label that is trying to promote the success of their artist ?
"Wouldn't any record company fight to have their artist have the exposure to millions? Only if they wanted their artist to succeed ! (sic)"