The Office of Fair Trading will announce today whether it plans to take any further legal action against the banks over unauthorised overdraft charges.
It will be the first time the trading watchdog has set out its position on whether it plans to continue its investigation into the charges following last month's ruling by the Supreme Court.
But the group is expected to say it has decided not to take any further action against the banks on the issue.
The Supreme Court ruled at the end of last month that the charges do not come under the OFT's regulation under unfair contract rules, dashing the hopes of thousands of consumers who had tried to reclaim them.
Customers who go into unauthorised overdraft or breach their agreed limit can be charged as much as £35 or more for a single bounced payment, although campaigners claim the actual cost to the banks could be as little as £2.50.
The charges generate around £2.6 billion of revenue a year for banks, and are used to subsidise free banking for other consumers.
The High Court test case was brought by the OFT and seven banks and a building society after thousands of consumers started to reclaim the charges.
The Government has indicated that despite the outcome of the ruling it will ensure the system of unauthorised overdraft charges is made fairer for consumers in the future.
It said it would work with the OFT and Financial Services Authority to create a new framework for fairer bank charges, but warned it would take action if a voluntary agreement with the banks could not be reached.
Martin Lewis, creator of MoneySavingExpert.com, which ran a campaign encouraging people to reclaim the charges, has called on the OFT to continue the fight to help people get refunds.
He said: "We know the OFT thinks charges are unfair, because it provisionally said so.
"The only issue is finding a law that allows the OFT to make a judgment on fairness.
"We believe there are regulations that could allow this: Regulation 5 of the Unfair Terms in Consumer Contracts Regulations, and Section 140 of the Consumer Credit Act. These laws even put the burden of proof on banks to prove fairness."