Amazon is tapping some of the biggest athletic apparel suppliers to foray into private label sportswear. The project is new and long-term contracts haven’t been signed yet. Manufacturers are producing small amounts of products for Amazon as part of a trial.

Amazon previously ventured into private label fashion, offering office clothing, jackets and dresses under names like Goodthreads and Paris Sunday. But pushing into active wear would bring fresh competition to some of the world’s biggest athletic brands.

Amazon also has been hiring staff with know-how in private-label athletic apparel. Amazon has developed its own brands in part because they fill gaps in its inventory. If customers are searching for a certain type of shoe or skirt, and don’t see much of a selection from established brands, Amazon wants to be able to offer its own options.

This also sends a message to brands reluctant to sell their full inventory on Amazon. If shoppers can’t find a brand’s products on the site, Amazon will make its own substitutes and become a competitor. The move may be unwelcome for active wear companies already struggling to stand out in a sea of competition and discounts. Online apparel sales accounted for 19 per cent of all apparel sales in 2016, up from 11 per cent in 2011.