Tor UK said it is now consulting with its authors about future plans and aims to start offering DRM-free e-books within the next three months.

The move has been interpreted as a watershed moment in the history of digital book publishing. Science fiction writer , who is published by Tor is the US, said that, in the long term, removing the requirement for DRM will lower the barrier to entry in ebook retail, allowing smaller retailers to compete effectively with the current major incumbents.

Meanwhile, Tor author dismissed suggestions that people will stop buying e-books after DRM has been dropped.

"As an author, I haven't seen any particular advantage to DRM-laden eBooks. DRM hasn't stopped my books from being out there on the dark side of the internet. Meanwhile, the people who do spend money to support me and my writing have been penalised for playing by the rules," he said.

"The idea that my readers will, after July, 'buy once, keep anywhere,' makes me happy."