Read more at BBC Radio 1’s Newsbeat site.
She told BBC Newsbeat: "I’ve been talking to some insiders and it’s not something that they haven’t been working on. I don’t actually know anything other than that.
I know it’s still going to be Abba music, because what else would it be? Come on, I wouldn’t do Mamma Mia 2 without Benny and Bjorn."