MEXICO CITY (Reuters) - Chinese fast-fashion giant Shein is launching its first branded credit card worldwide through a partnership with Mexican fintech Stori, the firms said on Tuesday, touting synergies that should help both expand in Latin America's second-largest economy.

The push will simultaneously aim to draw more Mexicans to the credit market, where they lag in access, as well as luring shoppers to the low-cost, quick-turnaround retailer's website.

Throughout Latin America, Shein has exploded in popularity in recent years, as it weighs plans to build a plant in Mexico and build out a distribution network in prime market Brazil.

The region has also seen a boom in small businesses which buy Shein clothing in bulk and re-sell it in physical storefronts.

Shein - valued at $66 billion in a fundraising round last year - has disrupted the fast-fashion industry with its low-cost model and rapid growth.

Mexico's e-commerce market was the fastest growing in the world last year, according to a study by the Mexican Online Sales Association (AMVO), with just over 40% of all online purchases being clothing.

The Shein credit card, a Mastercard ( MA ), will offer points to use on the retailer's website with every purchase. Clothing purchases on Shein's website will earn double points, the firms said in a statement.

Stori, a fintech offering services such as savings accounts that provide 15% yields and credit cards with near-total approval rates, has already scooped up 3 million clients in Mexico in the last four years.

The Shein card will only be available to new Stori clients and not existing ones, according to Stori's website.