At first glance, Sarah Jessica Parker is an unlikely champion of designer clothing for the masses.

Her Sex and the City character Carrie Bradshaw did, after all, single-handedly turn ￡500-a-pair Manolo Blahnik heels into a household name.

But the 43-year-old actress is leading a cut-price fashion revolution by lending her name to a brightly-coloured sun frock touted as the world's cheapest designer dress - at just ￡4.50.

The sun dress, which the actress wore at a recent New York premiere, is one of more than 1,000 items in her Bitten line (as in "bitten by the acting bug") at the retailing phenomenon Steve &Barry.

They include jeans, dresses, jackets, Tshirts, cashmere jumpers, shoes and lingerie. And all sell for ￡4.50 or less.

The shop was launched by childhood friends Steve Shore and Barry Prevor, both 44, in 1985.

They began by selling clothes with university logos but business really took off after they hit on the idea of attracting celebrities to help sell lowcost designer gear two years ago.

Steve &Barry's has no online store and doesn't even offer old-fashioned phone mail order.

But word of mouth has helped it build a network of 264 shops in 37 U.S. states, including one in Manhattan that is perpetually packed with British visitors.

The pair claim they keep prices low by opening in struggling shopping centres where they can negotiate cheaper rents and by manufacturing in countries such as China, India and Madagascar.

But they say they do not use sweatshops and rely on "razor-thin" profits, saving on advertising in the belief that the prices sell themselves.