The SME Alliance made the comments after a report from Sir Ross Cranston found that a scheme to compensate customers affected by the scandal at HBOS Reading had "serious shortcomings".
Sir Ross, a law professor at the London School of Economics, said that Lloyds, which took over HBOS in 2008, must go back to the drawing board and re-assess customers' compensation claims.
Six people, two of them former employees of HBOS, were convicted and sentenced to up to 12 years in prison for criminal misconduct between 2003 and 2007 at HBOS Reading.
Nikki Turner, outgoing director of SME Alliance, said: “While we welcome Sir Ross’s conclusions, and the commitment by Lloyds to review the cases again, we are concerned about how long this might take.
"It is nearly three years since the guilty verdicts were handed down, and a decade and a half since many of the frauds took place. Victims are suffering real hardship, many lost their businesses, homes and – in some cases – families. They need fair restitution now.
"“Lloyds, and António Horta-Osório in particular, might want to reflect on whether they have lived up to the promises they made nearly three years ago. It is important to note that the ‘distress and inconvenience’ payments from the bank were ones made without admitting any culpability or liability, and were only made on the condition of victims accepting onerous non-disclosure clauses and dropping any further claims.
"The bank also needs to open up the compensation process to those it has refused to help, and to those who may have opted out because of what Sir Ross describes as the ‘opacity’ of the scheme. This all needs to be actioned rapidly, fairly and transparently.
“We are grateful to Sir Ross and his team for their hard work, thoroughness and fairness. We also thank the FCA for pressurising Lloyds to finally appoint an independent arbiter.”
Sir Ross's independent report assessed the customer review, overseen by Professor Russel Griggs OBE, which the Lloyds Banking Group had set up to compensate victims of the HBOS Reading fraud.
Lloyds Banking Group said it accepts his main finding that “the methodology and process of the Customer Review did not achieve the purpose of delivering fair and reasonable offers of compensation”.
In a statement, Lloyds Banking Group said: "The group has apologised to those customers affected by the crimes at HBOS Reading and deeply regrets that customer concerns have not been adequately addressed by the operation of the customer review. The group is committed to implementing Sir Ross’s recommendations in full in order to put this right for customers.
Sir Ross Cranston’s review has concluded that while distress and inconvenience compensation was “generous, and beyond what a customer could hope to have been awarded under that head of loss by a court”, the review did not achieve its objective of giving all customers the confidence that they had received fair and reasonable outcomes in respect of the assessment of direct and consequential losses.
Lloyds Banking Group said it had accepted Sir Ross’s additional recommendations that it reconsiders all cases where an individual sought inclusion in the customer review on the basis that they acted as a de facto director and reconsiders eligibility for debt relief payments.
The group has also accepted that it must provide the Treasury Committee with copies of the Settlement Agreements that evolved from the initial version provided by Professor Griggs.
The group has said it will be guided by the victims, the APPG on Fair Business Banking, the SME Alliance and other stakeholders on how best to implement Sir Ross’s recommendation for a re-review, including how it is undertaken and which independent expert or experts should be appointed to lead that review.
The statement added: "We will provide our full support to ensure Sir Ross’s recommendations are delivered in full and transparently so that customers can have confidence that fair outcomes have been achieved."
Lloyds Banking Group Chief Executive António Horta-Osório said: “Our intention when we set up the Griggs Review was to deliver fair and reasonable outcomes for customers in a swift way that would be more generous than through the courts. Sir Ross has concluded that customers may not have received fair outcomes due to flaws in the review process. I am very sorry that this has happened.
"The group is committed to act on the recommendations made by Sir Ross, and will fully support giving customers the option of a voluntary re-review of direct and consequential losses. We will be guided by the victims, the APPG, the SME Alliance, Sir Ross and our regulators on the best way to achieve that. I want to emphasise my personal commitment to ensuring that those customers affected by the actions of individuals who have since been jailed for their crimes will get their claims properly addressed in an open and transparent manner.”