UPDATE 1- Japan's Softbank in talks for $12.8 bln Sprint stake - media

TOKYO, Oct 11 (Reuters) - Japanese mobile carrier Softbank Corp is in talks to buy more than two-thirds of U.S.-based telecoms company Sprint Nextel Corp , public broadcaster NHK said on Thursday, in a deal worth at least 1 trillion yen ($12.8 billion).

Softbank, which is valued at just over $40 billion, announced earlier this month it would buy smaller rival eAccess Ltd in a $1.84 billion deal as Japan's third-largest mobile carrier steps up its battle for market share with rival KDDI Corp .

Japanese media said a Sprint deal would make it cheaper for Softbank to procure smartphones and other mobile devices.

(Editing by and Ian Geoghegan)

((ian.geoghegan@thomsonreuters.com; Reuters Messaging: ian.geoghegan.thomsonreuters.com@reuters.net))