The technology - branded as Virtual Account Numbers by the US bank - generates a random, substitute account number for every online purchase, ensuring that the real account number is never compromised.

The bank is promoting its latest anti-fraud initiative alongside Citi Cards' zero-liability guarantee, which waives a customer's responsibility for any unauthorised charges to their account, in an effort to encourage more consumers to shop online.

Amy Radin, director, e-business, Citi Cards, comments: "Consumers gain peace of mind knowing that their personal credit card information never travels on the Internet. For online retailers, who generally bear the financial liability for fraudulent purchases, reduced online fraud equates to a better bottom line."

To use the technology, customers download the Virtual Account Numbers payment software after registering at www.citicards.com and assigning themselves a user name and password. When making a purchase, the customer enters that user name and password for authentication and with one click a random substitute credit card number is generated and transferred into the retailer's checkout form. Once used, the substitute number is not valid at any other retailer site. Each substitute number is tied to the cardholder's actual Citi Card account allowing them to access the purchase information when necessary.

The Orbiscom patented software can be used at any online retail site as well as for other purchases that do not require a physical credit card such as catalogue sales placed over the telephone.

Dublin-based Orbiscom customers include MBNA, Discover Card, First Data Corp, Allied Irish Bank, Carte Bleue, Swedbank, Abbey National, Societe Generale, and Credit Lyonnais.