Get Me Out Of Here launched on Sunday night and brought massive viewers to ITV.
"We are very happy with Holly presenting alongside Dec", the spokesperson continued.
Some 11 million people tuned in for the first episode - up 700,000 on past year, according to overnight ratings.
Elen Rees wrote: "I'm a Celebrity Get Me Out of Here is animal cruelty".
The figure is up 750,000 on last year and was the biggest overnight rating of the year besides the World Cup.More news: Fox News backs CNN in lawsuit against Trump, wants Acosta reinstated
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Willoughby is taking a break from her usual job on the This Morning couch with Schofield to fill in for Ant McPartlin alongside Dec Donnelly in the jungle, while Rochelle Humes takes her place on the ITV daytime show until she returns. Holly Willoughby is joining Donnelly as co-presenter for the new series, which will see the likes of football boss Harry Redknapp, DIY SOS host Nick Knowles, ex-EastEnders star Rita Simons and entertainer and actor John Barrowman compete to be crowned King or Queen of the Jungle.
When all the teams are complete, they'll both take part in a final head-to-head challenge which will see the winners move straight into the main camp Croc Creek, with the losers heading down to Snake Rock.
After ongoing rumours, ITV have confirmed that Holly Willoughby will not be replaced by another presenter before the end of this year's I'm A Celebrity.Get Me Out Of Here!. They're all friends and he's certain she'll be great - he'll be rooting for them all'.
But back to the task at hand, Emily Atack was selected to do the Bushtucker Trial called the Viper Pit, and the name alone was enough to turn us off it.