She joins musicians such as Jay-Z, Pharrell Williams and 50 Cent, who have also appeared in campaigns for the sports brand. Jamelia will be working on Reebok's RBK label, which fuses urban street fashion and sports. She is to promote NFL apparel, which includes velour tracksuits, satin sleeveless jackets, hot pants and T-shirts.
Photographs of her wearing the clothes have been shot by Daniela Federici and will appear in stores in the run up to Christmas. She will also carry out in-store appearances and work as a fashion consultant to Reebok to develop further RBK collections.
Reebok said that it was not just Jamelia's celebrity that had helped her win the contract.
Michael Price, marketing director for Reebok in the UK, said: "We've signed the UK's biggest and most beautiful music and fashion icon for young women. Plus she has the longest legs in showbiz, helping this campaign to really kick some butt."
Jamelia's success as a singer has seen her being snapped up by Pretty Polly, where she took over from former S Club star Rachel Stevens.
Reebok recently appointed Leagas Delaney to relaunch its European football campaign and to work on RBK. Globally, it retains Omnicom Group agency the Arnell Group, but it is reported to have shifted some of the account to an independent agency called McGarry Bowen.
Last week, Reebok said that it was introducing a second edition of its Pump shoes, where the shoe inflates to fit around the wearer's foot. The first Pump shoe, introduced in 1989, sold 20m pairs across the globe.
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