Six men, one of whom worked for Halifax Bank of Scotland (HBOS) – part of the Lloyds group – were jailed in February for stealing money from small business clients.
The Financial Conduct Authority (FCA) has announced that it is re-opening an enquiry into the case.
Lloyds has already set aside at least £250m to cover other costs arising from the case, which was centred on the HBOS office in the Berkshire town.
António Horta-Osório, chief executive of Lloyds Banking Group, said: “As I have stated before, we would like to express our deep regret and apologies to any customers directly affected by the criminal behaviour of these individuals.
“We are absolutely determined that victims of the crimes committed at HBOS Reading are fairly, swiftly and appropriately compensated. We take responsibility for putting right the wrongs that were committed at HBOS Reading at the time.”