Willoughby said in a statement: “I couldn’t be more excited to have been asked to stand alongside Dec for the next jungle adventure.
“I love Ant and want to send him my best wishes and support for a continued recovery. These are big shoes, not to fill, but just to keep warm for a little bit ... Honestly, I’m a huge fan of ‘I’m a Celebrity’ and actually feel like I’ve won a competition to go and hang out on my favourite show! When is it a good time to tell Dec I’m scared of everything that moves?!”
Donnelly said: “I am hugely grateful to Holly for agreeing to accompany me to Australia this year. She was at the top of my list and I’m thrilled she said yes.
“It will be a different kind of series but we will try our best to ensure it is no less fun and eventful for our loyal viewers.
“I am also pleased to hear Holly is scared of everything. I am almost stupidly excited at the thought of watching her during the eating trials!”
ITV’s director of television Kevin Lygo said: “Holly is a brilliant presenter with a wicked sense of humour who has always enjoyed a great friendship and rapport with Ant and Dec - I have no doubt she will take to Jungle life, if not the critters, really quickly.”
Ant McPartlin announced he will be taking a break from television presenting duties until 2019 follwoing a drink-driving charge earlier this year.