The Guardian newspaper reports that around 100 customers were affected by the gremlins, and all were using Abbey’s online business banking service.

The bank, owned by Spanish group Banco Santander, responded by saying that the fault was down to a design flaw in the business website, rather than an out and out security breach.

The specialist IT news site Silicon.com reports that Abbey says the problems centered on the platform having separate lists of authorized payments for each registered user rather than for each account, which sometimes meant that the different payment lists failed to synchronize with one another.