Only nine celebrities have started filming the ITV1 reality show and it is unclear why Starr has not taken part as planned.
According to The Sun, producers are still hopeful that Starr will join Mark Wright, Dougie Poynter and the other celebrities at a later date.
Simon Cowell's close friend Sinitta also pulled out of the show at the last minute earlier this week.
Former Fun House host Pat Sharp is on standby to replace celebrities, so he may be sent into the show if Starr doesn't decide to take part.
I'm a Celebrity's 11th series starts on Sunday at 9pm on ITV1.
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