Timmy Mallett is 1000/1 to top the UK singles charts at Christmas.

The former children's TV presenter - who had a hit with Itsy Bitsy Teeny Weeny Yellow Polka Dot Bikini in 1990 - is currently working with I'm A Celebrity... camp mate David Van Day on a track called Biff Baff Boff.

Despite being convinced they are destined for chart success with the song, written about their time in the Australian jungle, bookmakers are less hopeful and have made them rank outsiders to take the prestigious festive top slot.

Rupert Adams, spokesperson for bookmaker's William Hill said: "Even if Mr. Mallett decides to produce a single, we think it is extremely unlikely that you will have to hear it because we suspect that it will sink like a stone."

Programme hosts Ant and Dec have mocked the song, which received a lukewarm reception from the other contestants, saying: "Any little melody the contestants get in their head, they think it's a future number one!

"And it obviously isn't. It's rubbish! We've all heard it."