E-commerce giant Rakuten and retail behemoth Walmart are taking aim at Amazon in a partnership that will see the two companies launch an online grocery delivery service in Japan while offering e-readers, e-books and audiobooks to American Walmart customers.

The move, announced Friday, will see Rakuten Inc. team up with Wal-Mart Stores Inc. subsidiary and supermarket chain Seiyu GK. The joint venture will replace and expand Walmart's existing grocery delivery service with an operation called Rakuten Seiyu Netsuper. The service, with a planned launch in the latter half of this year, will allow customers to place orders on Rakuten's online marketplace. The venture will open a warehouse to handle orders in addition to using existing Seiyu stores.

The collaboration will also allow Walmart to take direct aim at Amazon.com Inc.'s Kindle by bringing Rakuten-owned Kobo's e-reader to its U.S. stores, along with a catalog of nearly 6 million e-book and audiobook titles to Walmart.com customers.