Apparel prices in the US have fallen to almost their lowest level for four years as more and more clothing firms switch to cheap offshore manufacturing and fierce competition forces stores to slash prices.

According to the latest consumer price index report from the US Department of Labour, clothing prices slipped one per cent last month following a 0.9 per cent slide in June and a 0.6 per cent fall in May.

Those slides combined with earlier falls means clothing prices have fallen 3.2 per cent from the year-ago period as firms who have switched their operations to countries with cheap labour pass on the savings of lower production costs.

Industry observers and economists say that move combined with greater competition at retail level has kept prices down with many shoppers tending to buy apparel from discount stores or shopping only during sale periods.

Commentators also point out that apparel prices could fall even further if trade chiefs were to increase textile quotas and reduce import duties as well as cut other strict trade regulations.