Amex, like rivals Visa and MasterCard, says it recognises that the payments industry is undergoing fundamental change as commerce moves online.

To help fend off competition from the likes of PayPal and Google, as well as a raft of new entrants, last year it acquired the Revolution Money platform and used it as the basis of a digital payment and commerce offering called Serve.

The firm has also made a number of other digital moves, cutting a deal with Facebook, filing a patent for a system and method for using loyalty rewards as a currency, investing in mobile outfit Payfone and buying Sometrics, a virtual currency vendor.

Now it is promising a "multi-year digital commerce initiative designed to help identify and develop innovative technologies that will help accelerate the company's digital transformation and strengthen connections to a growing base of customers around the globe".

As well as earmarking $100 million for investment, an office has been established in Silicon Valley from which the initiative will be managed by Harshul Sanghi, who was recently appointed as managing partner, enterprise growth group. Sanghi previously ran Motorola Mobility Ventures.

Dan Schulman, group president, enterprise growth, American Express, says: "American Express is a 162 year old company that has continuously reinvented itself. As we enter the next chapter in our history, we recognize the need to work with emerging technology companies to inspire change, encourage innovation, and ultimately deliver the best products and services to our customers."

Sanghi adds: "The payments industry is undergoing a fundamental change as the very nature of commerce is redefined. We believe our global network of businesses and consumers, international employee base, world-class customer service and data analytics will provide a significant advantage to potential portfolio companies."