JK Rowling will "explore new territory" in her coming work.

The renowned author has published seven books in her Harry Potter young adult fantasy novel series.

JK, who has sold 450 million copies of her Harry Potter tomes worldwide, will now enter a new literary realm.

USA Today reports that the author will write for adults.

"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," JK said in a statement.

"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."

JK's currently untitled adult novel will be published by Little, Brown and distributed worldwide.

Neither a print or release date for the tome has been released.

JK's Harry Potter books have been transformed into a blockbuster movie franchise, with eight films starring Daniel Radcliffe earning billions of dollars internationally.