Payments made by American Express' business customers on its FX International Payments (FXIP) platform will now be routed through Ripple's enterprise blockchain network, RippleNet.
Blockchain — otherwise known as distributed ledger technology — allows vast amounts of data to be stored on a dispersed network of computers around the world, rather than on one centralized server.
It was originally used to record all bitcoin transactions but increasingly businesses are finding alternative uses for the technology, such as payments, trade finance and identity verification.
"This collaboration with Ripple and Santander represents the next step forward on our blockchain journey, evolving the way we move money around the world," Marc Gordon, executive vice president and chief information officer at American Express, said in a statement Thursday.
American Express' blockchain project will initially allow customers in the U.S. to connect instant, traceable cross-border non-card payments to U.K. Santander bank accounts.
"This blockchain solution opens up a new channel between the U.S. and the U.K. and presents significant opportunity for payments globally", Jose Luis Calderon, global head of global transaction banking at Santander, said in a statement Thursday.
The distributed ledger platform will enable all parties involved to keep track of a transaction's status and cost.
Ripple CEO Brad Garlinghouse said that its blockchain network would allow the business customers of financial services firms to move money in "real-time."
"We're taking a huge step forward with American Express and Santander in solving the problems corporate customers experience with global payments. Transfers that used to take days will be completed in real-time, allowing money to move as fast as business today," Garlinghouse said in a statement Thursday.
Both American Express and Santander suggested the blockchain project could eventually be extended worldwide.
Ripple said that it is has tested a means of speeding up payments with its cryptocurrency, XRP, and that this would become a feature in its partnerships with banks and other financial companies further down the line.
"The XRP currency will come into play later on in the evolutionary dynamics and the other players," Marcus Treacher, global head of strategic accounts at Ripple, told CNBC in an interview.
"The technology we have developed, it separated a connection from the cryptocurrency or the token. So what that means is that a bank or non-bank like AMEX can use Ripple to connect and just exchange value from one fiat currency to another directly, without the need for any intermediate blockchain currency."
Some banking executives have raised concern about cryptocurrencies in recent weeks.
Last month, UBS CEO Sergio Ermotti told CNBC he was "not necessarily" a believer in cryptocurrencies but that he saw a future for blockchain. Credit Suisse CEO Tidjane Thiam went as far as to describe the world's largest cryptocurrency bitcoin as "the very definition of a bubble."
And, most notably, JPMorgan's Jamie Dimon has been particularly critical of bitcoin, and last month said that anyone "stupid enough to buy bitcoin" would "pay the price for it one day."