An insider said, "Donatella was a big fan of the girls back in the day and as soon as she heard that a reunion was on the cards she submitted her ideas. There will be several different 'looks' for each of them and the clothes will be worth over £200,000 [about $400,000].

The Girls are said to be anxious about fitting into the costumes, which will allow them "to retain their band personas but in a much less obvious way than before," said the snitch. "Mel C won't be wearing ill-fitting sportswear - instead she'll have a really sexy wardrobe. Emma Bunton will wear stunning, elegant dresses with a playful touch. Donatella thinks they look better than many bands half their age and should show that off."

The tour begins in December. But the Girls will start rehearsing in Los Angeles in September