PARIS (Reuters) - Two French banks and a group of retailers are teaming up to launch a smartphone app next year that will help customers pay for purchases in stores and online, gather loyalty benefits or transfer money using a single "mobile payment solution".


France's biggest bank BNP Paribas and cooperative lender Credit Mutuel plan to merge their "digital wallets" WA! and Fivory into a single platform, they said on Thursday.


Financial services companies and internet giants such as Google and PayPal are looking to capitalize on the growing use of smartphones by providing apps that house credit and debit cards, coupons and store loyalty program details virtually.


BNP Paribas and Credit Mutuel will each own 40 percent in the venture, which involves other partners, including retailers Auchan and Carrefour and credit-card company Mastercard. Over time, they hope it will attract more.


"This structure leaves room for one or two big retailers or large industrials that could enter the capital of the company," Thierry Laborde, BNP Paribas' Deputy Chief Operating Officer and Head of Domestic Markets, told Reuters over the phone.


Initially, customers will be able to use the digital wallet at more than 20,000 retailers in France.

A brand name for the app is due to be announced by the end of the year. It is expected to be available in early 2017.

(Reporting by Maya Nikolaeva and Julien Ponthus; Editing by Mark Potter)