Una, 32, confirmed that she will be taking part in the challenging reality TV show on Instagram earlier today (20 December) by posting a photo of herself with Tom.
She wrote: "I can now announce that I am in fact taking part in next years @splashitv #excited."
The image shows Una wearing a figure-flattering red one piece and looking far too glamorous for a day at the local swimming pool.
She is stood beside Splash! presenter Tom, who is wearing a tight green T-shirt and pulling a cheeky smile for the camera.
The songstress - who is married to rugby player Ben Foden - will be putting her microphone to one side in the coming weeks, so that she can learn how to dive like a pro and compete against her fellow celebs.
Although the rest of the Splash! competitors are still unknown, it has been rumoured that model Danielle Lloyd and Hollyoaks star Gemma Merna will be taking to the diving board in the New Year.
Former GMTV presenter Anna Williamson and Diversity dancer Perri Kiely were also spotted practising their skills at a pool with Tom recently, hinting that they too could be taking part in the forthcoming series.
But with those names still up in the air and unconfirmed, we've already found ourselves rooting for Una to take home the winner's title.
Maybe she could give us a few dance moves from her routines with The Saturdays while she's stood on that diving board?!
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