Retailers may have to send a parcel to USA more often.

The news comes after new research shows that a quarter of New Yorkers are shopping online after leaving high street stores empty-handed.

Research carried out on behalf of Envirosell and RichRelevance, found that half of shoppers in New York and London leave high street shops having bought nothing.

The survey found half of these people then carry on with their search for items online.

And it was New Yorkers who were found to be much more likely than UK shoppers to carry out some online research, prior to their shopping trip.

Just a third of those polled in London had looked at products online before leaving their house, compared to 85 per cent of shoppers in the Big Apple.

Envirosell founder and chief executive Paco Underhill said: "The growth of the internet has meant that the consumer is now not only more empowered, but often three or four steps ahead."