The UK's biggest banks are set to increase their profits this year, but financial hits from reforms linked to past scandals are likely to keep coming, according to a rating agency.Barclays, HSBC, Lloyds Banking Group and the Royal Bank of Scotland are set to focus on improving returns and putting sustainable business regimes in place after completing restructuring drives linked to the financial crisis, Standard & Poor's said.Banks have been reinforcing balance sheets, off-loading non-core businesses and putting in place safeguards to prevent a recurrence of controversies such as PPI mis-selling and Libor rate-rigging allegations.However, S&P said the four big banks booked more than £14bn in one-off charges in 2013.Worse even, "we see more to come in 2014 and beyond," S&P added. "This will continue to drag on statutory earnings recovery."S&P said banks were now facing a period of preparation for regulatory changes such as even stricter capital standards and the ring-fencing of retail and small business banking from more riskier activities such as proprietary trading or securities underwriting."In our view, to achieve the business transformation targets they have set themselves, all four banking groups will need to implement substantial changes and will incur further material costs," S&P said."That said, Lloyds and HSBC appear to us to be more advanced in their longer-term plans and better placed to capitalise on the UK's economic recovery."RBS remained loss-making on a statutory basis for the sixth consecutive year and has the most work to do in terms of returning to sustainable profitability, in our view."Meanwhile, Barclays is in the midst of significant restructuring and organisational change which we believe may be a protracted process."PW