There had previously been rumours that the Britain's Got Talent judge was being lined up for the programme, but her involvement was only confirmed today (March 21) on ITV's This Morning.
Speaking to hosts Holly Willoughby and Phillip Schofield, she said: "I am [hosting] - it's terrifying. We haven't signed on the dotted line yet, but I am and I'm not sure if I'm supposed to talk about it!"
Holden made light of her recent near-death experience during the birth of her child, saying: "As I have a West End background, and I nearly met Jesus the other week, I'm the best qualified."
Talking about what stage the competition had reached, she commented: "They've gone all over the country and Andrew said they've even had some girls auditioning as well... And I'm not sure they've sorted out the judging panel yet, but it's going to be a huge arena tour and it'll go worldwide."
It was recently announced that Melanie C and Jason Donovan will be judges on part of the show.
Lloyd Webber has revealed that females are eligible for the title role.