Online shopping giant Amazon said Wednesday that it will launch a Japanese-language version of its hugely popular Kindle next month as it looks to break into the largely untapped Japanese e-book market.

The retailer's long-awaited announcement comes a day after Apple unveiled its new iPad Mini, the latest volley in the battle for the multi-billion-dollar tablet sector.

US-based Amazon said in a statement that it would begin selling 50,000 Japanese-language titles from Thursday, while its Kindle Paperwhite became available for pre-order on Wednesday. It is expected to start shipping on November 19.

A Japanese-capable Kindle app will be available for computers, tablets and smartphones from Thursday, the company said.

The wifi only Paperwhite will have a price tag of 8,480 yen ($107), while the 3G-equipped version will sell at 12,980 yen, Amazon said. Both prices are lower than on the US website.

The new Kindle Fire HD with an 8.9-inch (22.6-centimetre) display that was unveiled in the United States last month will be released in December in Japan. Japan's existing e-book market is largely a niche affair, mostly comprising comic books for mobile phone users.

Only a limited number of novels and non-fiction titles have been digitised in a country where the unique language protects publishers from foreign competition.

Amazon's announcement of 50,000 titles is broadly in line with Sony's nearly 60,000 offered in its own e-book store for use with a proprietary device, but falls well short of the "millions" of titles Amazon.com offers to US customers.

In July e-commerce giant Rakuten launched its Kobo e-reader in Japan, saying it would initially be able to offer around 30,000 titles, but was aiming to grow that figure to 1.5 million over the coming years.

Japanese publishers, already facing falling paper book sales, have so far been reluctant to digitise their books for fear that e-books could kill physical sales.

Experts say Amazon's entry could trigger a significant expansion of available digital book titles over the next two to three years.