Holly Willoughby beams as she waves to the camera days before jetting off the I'm A Celebrity

Holly Willoughby beamed as she was spotted out and about in London days before jetting off to Australia for I’m A Celebrity.

The This Morning presenter is swapping the studio sofa for live Down Under as she prepares to host the popular jungle show with Declan Donnelly.

Willoughby, 37, was all smiles as she walked around in the capital on Thursday, already in holiday mode with Ray Ban sunglasses.

Just yesterday, Willoughby said goodbye to her closest friends as she gets ready to jet off for her three-week stint, showing off a good luck cake made for her.

Posing next to the chocolate dessert, Willoughby wrote: “Mmmmmm yummy .... my girls know what I like... thank you beautiful ladies @ruby1kid @shishib #nikidemetz and @emmaleebunton.”

It has also been claimed that the star is stepping up to the plate as a “favour” to her long-time friend McPartlin, who quit his TV commitments earlier in the year .

Extra Camp host Joe Swash told the Daily Mirror: “She's such good friends with the boys, and it's someone doing them a favour, it's not someone going in to try and enhance their career.

“Holly's so good at what she does, she'll be amazing, and I'm looking forward to it.”

Fans are already on tenterhooks as they wait to find out the famous faces taking part in this year’s series, which kicks off next weekend.

I’m A Celebrity returns Sunday November 18 at 9pm on ITV.