The online retailer said it has sold 114 e-books in 2012 for every 100 printed books, including both hardcover and paperback books and excluding free e-books.

It hit the same milestone in the US four years after introducing the Kindle.

Kindle EU vice president Jorrit Van der Meulen said: "To reach this landmark after just two years in the UK is remarkable and shows how quickly UK readers are embracing Kindle."

The company said British Kindle users are buying four times the number of books they did prior to owning a Kindle, but that Kindle owners continue to buy physical books as well.

It said it had seen a four-fold increase in indepdendent UK authors and publishers using its self-publishing platform Kindle Direct Publishing (KDP).

The company’s biggest selling author, EL James, who wrote Fifty Shades of Grey, is a former KDP author.

Her print and Kindle sales combined have eclipsed Harry Potter author JK Rowling’s total sales.

James has sold more than two million Kindle books in just four months.