Harry Potter author J.K. Rowling has announced plans for her first 'adult' novel and she insists it will be be very different to her books about the boy wizard.

The seven Potter books have turned Rowling into one of the world's richest women and now she's hoping her literary success will continue as she plots her next project with a new publisher.

A statement from the writer reads, "Although I've enjoyed writing it every bit as much, my next book will be very different to the Harry Potter series, which has been published so brilliantly by Bloomsbury and my other publishers around the world.

"The freedom to explore new territory is a gift that Harry's success has brought me, and with that new territory it seemed a logical progression to have a new publisher.

"I am delighted to have a second publishing home in Little, Brown, and a publishing team that will be a great partner in this new phase of my writing life."