Mariah Carey’s All I Want For Christmas Is You continues to break records 28 years after its release, but the singer’s long-time collaborator has sparked controversy by throwing cold water over the song’s origin story.

Carey told Billboard in 2017 that she wrote the song, which this year marked Christmas Eve by achieving the most streams in a single day on Spotify, as a kid on her “little Casio keyboard”.

But the song’s producer and co-writer Walter Afanasieff, who also produced Celine Dion’s My Heart Will Go On, called out Carey for her “tall tale”.

Appearing on the Hot Takes & Deep Dives podcast, Afanasieff said Carey started to create an “alternate reality” about the song’s origins about 15 years after it came out.

Both Afanasieff and Carey are equally, and solely, credited for the hit Christmas song.

“I’m always grateful to Mariah for having the wherewithal and the … staying power to be the Christmas Queen every year,” he said.

“But she doesn’t play anything. She doesn’t play keyboard or piano or she doesn’t understand music. She doesn’t know chord changes and music theory or anything like that.

“So to claim that she wrote a very complicated chord structured song with her finger on a Casio keyboard when she was a little girl, it’s kind of a tall tale.”

Afanasieff said Carey wrote the lyrics and helped create the melodies, buthe gave himself credit for writing all of the music and the chords.

Carey hits back

After Afanasieff made his comments, a representative for Carey denied the singer had ever claimed she wrote the song as a child.

“Mariah has never claimed to write All I Want for Christmas by herself or as a child. She has always credited Walter, as he is cited as a writer on the song, so that would be ridiculous,” the representative told The New York Post.

“Not sure where that rumour came from, but Mariah is very respectful of writers and the craft, as she is a songwriter herself.”

Carey backed herself up by posting a 1994 VH1 interview where she explained the writing process with Afanasieff to her Instagram story.

Long-time feud

Afanasieff likened the differing stories on the creation of All I Want For Christmas Is You to Carey’s abuse allegations against ex-husband, former Sony head Tommy Mottola.

Afanasieff said the singer was “bitter” Afanasieff didn’t follow her when she left Mottola and Sony, and didn’t speak to him for 20 years until she needed his permission to produce a children’s book based on their hit song.

It had been so long since the two had spoken, Afanasieff said he initially thought the call was a joke, but once he realised it was legitimate he asked Carey to collaborate on more songs in exchange for giving his permission to use the book.

The children’s picture book hit shelves in 2015, but Afanasieff said he hasn’t heard back from Carey about any possible collaborations.