Sony, battling Amazon and Apple in the electronic book reader race, unveiled its latest devices on Wednesday and expanded their availability to Australia, China, Italy, Japan and Spain.

Sony cut the size and weight of all three of its e-readers while expanding the use of touchscreens to all models -- allowing users to turn pages with a swipe of the finger like the Apple iPad.

The Japanese electronics giant increased the price of its cheapest e-reader, the Reader Pocket Edition, by 29 dollars while adding a touchscreen.

At 179 dollars, the Reader Pocket Edition, which features a five-inch screen, is 40 dollars more than Amazon's cheapest Kindle e-reader and 30 dollars more than US bookstore chain Barnes & Noble's device, the Nook.

The cheapest iPad costs 499 dollars but boasts a color screen and other features while the Sony Reader and the Kindle both use black-and-white e-ink technology.

The new Reader Touch Edition features a six-inch touchscreen and costs 229 dollars while the new Reader Daily Edition has a seven-inch touchscreen and Wi-Fi or 3G connectivity and costs 299 dollars.

Steve Haber, president of Sony's Digital Reading Business Division, said the company was also targeting "previously untapped markets."

"We take a thoughtful approach to country expansion, including Italy, Spain, Australia, Japan and China, working with local bookstores to ensure content is compatible, relevant and in the appropriate language for each market," he said.

Sony also said it was developing applications for the iPhone and Android mobile platform to allow users to read books from its Reader Store on those devices.

Sony said the new Reader Pocket Edition and new Reader Touch Edition are available immediately while the new Reader Daily Edition will be out in time for end-of-the-year holidays.

Amazon unveiled two new versions of the Kindle in late July, including one that sells for 139 dollars, its lowest price yet.

Staples announced Tuesday it will begin selling the Kindle this year, making the US office supply chain the second brick-and-mortar store to offer the device after retail giant Target.