Geri Horner is reportedly determined to wear ''age-appropriate costumes'' during the Spice Girls' comeback tour.

The 46-year-old pop star turned heads with some of her eye-popping outfits in the 90s - including her famous Union Jack dress - but she is now keen to adopt a more conservative look for the group's much-hyped reunion.

A source explained: ''All the girls have fully embraced this zeitgeist reunion, even if it means wearing clothes they wouldn't ­necessarily pluck from their own wardrobes.

''But Geri is a married woman, with kids of her own, and isn't so keen to revert back to the Ginger Spice of old.

''Understandably she wants to look more age-appropriate.

''She doesn't want to be prancing around the stage in a sequinned Union Flag mini-dress with her boobs out and wearing leather knee-high boots.

''Fans have been taking the mick out of her sedate, lady-of-the-manor look while even the girls have made a couple of jokey remarks about her posh new Boden housewife aesthetic.''

Acclaimed theatrical designer Gabriella Slade has been chosen to select the outfits for the band's comeback tour.

But Geri - who has kids Bluebell, 12, and Montague, two - is keen to present a more refined image of herself.

Speaking to The Sun on Sunday newspaper, the insider shared: ''Gabriella has done a brilliant job on the costume front, and she and Geri have provisionally agreed on a more refined yet theatrical version of that [Union Jack] dress.''

Meanwhile, it was recently reported that Mel C is taking the lead when it comes to the Spice Girls' musical direction for their tour.

The singer - who is known as Sporty Spice in the group - has made it her ''priority'' to ensure that she and her bandmates Geri, Mel B and Emma Bunton's vocals are in tip-top shape by using the same musical director she worked alongside on her solo music.

A source said: ''The girls each have a House of Spice theme complete with groups of dancers branded as Baby, Scary, Ginger and Sporty, which will certainly entertain.

''But Mel insisted she brought in a musical director she has worked closely with on her solo material to boost the vocal performances and make sure the music hits the right note.''