Madonna has been accused of copying designs for her tour merchandise from the fashion brand set up by famed Sex And The City stylist Patricia Field.

Field, who also worked on Tv series Ugly Betty and won an Oscar nomination for the costumes she put together for hit movie The Devil Wears Prada, has set up a self-titled clothing and accessories line and owns a boutique store in New York City.

The super-stylist's employees have now accused pop singer Madonna of copying one of her designs for merchandise sold on her recently completed Mdna world tour.

A post on Field's official blog features a picture of black caps emblazoned with the word Vogue which were sold at Madonna's recent Madison Square Garden gigs in New York City, alongside a message alleging the design is similar to one featured in Field's line of hats and T-shirts.

The message, titled Madonna Stole Our Vogue Hats, reads, "During Madonna's performance of her 2012 World Tour to promote her latest Cd, Mdna at Madison Square Garden this past year, one of our spies discovered... She is selling exact replicas of our Vogue hat as part of her tour merchandise!... Our own Patricia Field stylist, Hiraku, designed the snap back and we sell it as a T-shirt, headband and a beanie as well. They've been going like hotcakes here at the store and have become a staple of the Patricia Field brand this year. We get requests to send them to clients everywhere worldwide and people ask for them by name when they come into the store... Madonna is a thief! Do you really need an extra few thousand dollars? Shame, shame for stealing from those that inspire you!... Are we right to be offended by this, or should we just forget about it and move on?"