By Elizabeth Howcroft

PARIS, Jan 14 (Reuters) - Visa is working to integrate stablecoins into existing payment systems, seeing an opportunity to maintain its market leadership as these tokens gain traction, Visa's head of crypto, Cuy Sheffield, told Reuters.

Stablecoins, cryptocurrencies typically pegged to the U.S. dollar, allow funds to be moved outside traditional banking systems. While their circulation has surged, led by El Salvador-based Tether's USDT with around $187 billion tokens in circulation, mainstream merchant acceptance remains limited.

Even if new payments systems are built using the technology behind stablecoins, "you still have to come back and connect to the existing merchant acceptance ecosystem if you want that product to be used," Sheffield said, referring to the current network of sellers that accepts payments.

NO CURRENT 'MERCHANT ACCEPTANCE AT SCALE'

Visa already has various stablecoin-related initiatives, including stablecoin-linked payment cards. In December it launched a pilot programme to allow some U.S. banks to settle with Visa using Circle's stablecoin, USDC.

Currently, there's no "merchant acceptance at scale" allowing holders to spend their stablecoins, Sheffield said.

This means that companies "need Visa's products and services more than ever to be able to actually get real customers using them," he said.

Visa's stablecoin settlement volumes have hit $4.5 billion in annualised run rate, a small fraction of the $14.2 trillion in annual payments volume Visa processed last year.

"But this is growing significantly month over month," Sheffield said. "We're seeing demand, and it's mostly this class of stablecoin-linked card providers."

SOME BANKS CONSIDER LAUNCHING THEIR OWN STABLECOINS

Some banks, including Goldman Sachs, UBS and Citi, last year said they were exploring launching their own stablecoin, following warnings that stablecoins could potentially undermine the role of commercial banks in global payment flows.

European banks, including ING and UniCredit, have formed a company to launch a euro-pegged stablecoin, to counter U.S. dominance in digital payments.

Visa's Sheffield said he was excited about euro-backed stablecoins.

"I think the stablecoin story shouldn't just be about dollars," he said.

HIGH-FREQUENCY TRADERS DOMINATE MARKET

There are more than $270 billion worth of stablecoins in circulation, more than twice the $120 billion from two years ago, according to a data website run by Visa and blockchain analysts Allium Labs.

Still, in a note last year, JPMorgan analysts said the idea of stablecoins replacing traditional money was far from reality.

Of $47 trillion in stablecoin transaction volume recorded on blockchain, Visa's website cited $10.4 trillion as "adjusted" volume.

Sheffield said the figure was revised down to remove volumes from high-frequency traders who arbitrage across different exchanges, as well as other non-payment activity.

(Reporting by Elizabeth Howcroft; Editing by Bernadette Baum)

((Email: elizabeth.howcroft@thomsonreuters.com))