Several apparel and footwear makers, including Steve Madden, Asics and Columbia Sportswear, are challenging an alleged disparity in tariffs between men's and women's wear.

The companies have filed lawsuits against the federal Government, and could reclaim close to US$1bn worth of tariffs based on gender differences, according to the International Herald Tribune.

They claim there is no apparent pattern to the tariffs, and that they penalise both men and women in different instances.

The lawsuit reportedly accuses the US government of earning $2.5m from discriminatory tariffs on underpants last year, $93m from cotton shirts, $16m from silk shirts and $71m from shoes with leather tops.