will.i.am thinks Rita Ora will one day emulate the success of Stella McCartney.

He explained: "She's up there with people like Pharrell Williams in terms of products. And the thing is she's only 24. In another ten years, where will she be? I see her as being a Stella McCartney."

The pair first met when she was just 18, and Will recalled being shocked to learn that she was so young.

He told the Daily Mail newspaper: "I didn't believe she was 18. Or I didn't want to believe she was 18. When you see someone who's really hot, you don't want them to be that age. I remember saying, 'Please tell me you're not 18.'"

Rita, who will also star on the show alongside Tom Jones and Ricky Wilson, the lead singer of the Kaiser Chiefs, revealed Will has become one of her mentors.

She said: "He's been a great mentor, completely honest. He's one of those people you'd answer the phone to after midnight. There are only a few people in this industry who really care about others, and he's one of them."