Mamma Mia 2 has grossed around $90 million worldwide since its release at the end of last week, with the soundtrack album also on course to hit No1 in the UK on Friday.
One of the most popular musical numbers is When I Kissed The Teacher, led by James as the young Donna near the very start of the film.
The choreography sees her planting a cheeky kiss on Celia Imrie’s tutor character – leading to chatter online that Donna could be bisexual.
Responding to the idea that Donna – played as an older woman by Meryl Streep – is a “bisexual icon”, James told The Hollywood Reporter: “God, wow! I had no idea. That’s amazing.
“That’s so interesting because I never thought about that.”
She added: “I think in a way the song was more of an act of rebellion, rather than literal.
“It was sort of like two fingers up to the establishment, and she breaks out of her valedictorian gown, being the first female valedictorian, and breaks out into a rock song.
“But that’s pretty cool. I kind of love that. I think it just shows what it can mean to everyone and all sorts of people.
“I love it to be celebrated in that way. I’m sure Donna would have been up for it.”
In the same interview, James spoke about work on her next project – another Richard Curtis movie; this time focussing on the music of The Beatles.
“I just finished shooting a movie with Danny Boyle and Richard Curtis, which was all centered around the music of The Beatles. It’s not a musical but it’s kind of a comedy/love/music story,” she teased.
“I loved working with Danny Boyle. He’s one-of-a-kind in his approach and passion and is a real visionary. For directors I’ve always wanted to work with, he’s in like the top five.”
The project also stars Kate McKinnon and is expected for release in the autumn of 2019.
Mamma Mia: Here We Go Again is out now.