The reality personalities will release a cover of Wham!'s 'Last Christmas' for charity on December 18.
Jessica Wright said: "It's really exciting. I love singing, it's always been one of my dreams. Everyone's getting in the Christmas spirit."
The track has been given odds of 6/1 to top the Christmas chart, behind X Factor favourite Marcus Collins, whose chances are highest at 3/1.
Cast members have also recorded their own unique version of the show's theme song 'The Only Way Is Up', which will serve as the single's B-side. The original, by Yazz and The Plastic Population, spent five weeks at number one in 1988.
All profits from the single will go to Text SANTA, a major new charity initiative set up by ITV, which aims to raise money and awareness for a group of well deserving charities, including Crisis, Samaritans and Great Ormond Street Hospital.
It was recently revealed that TOWIE star Mark Wright will compete on this year's I'm A Celebrity.
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