The Financial Conduct Authority is to review the success of the handling of complaints relating to mis-sold payment protection insurance and is once again considering a time limit on compensation.
PPI is the most expensive mis-selling scandal in financial history: 14 million claims have been received since 2011, costing lenders £17bn in compensation.
The FCA said it is analysing trends in complaints and will then "consider whether further interventions may be appropriate".
The regulatory body said: "While this work continues, the FCA expects firms to continue to deal with PPI complaints in accordance with our requirements."
Recently the UK's chief financial ombudsman said banks would be paying PPI compensation for years to come; FOS receives 4,000 new cases every week.
Imposing time limits on complaints could help draw the scandal to a close. A possible FCA-imposed time limit on PPI complaints was first reported on back in 2013, with the British Bankers' Association pushing for a May 2014 deadline.
The FCA is also looking at a consumer awareness campaign. It will announce the findings of the review this summer.