Treasury select committee chair Nicky Morgan has demanded the FCA release its full report on RBS' treatment of business customers.
Morgan has written to Andrew Bailey, chief executive of the City watchdog, calling for him to hand over its findings on the bank's Global Restructuring Group. Her actions come after a leaked document suggested investigators found "inappropriate action" was experienced by 92 per cent of GRG's customers.
The FCA told the Treasury select committee in November 2016 that a ‘full account’ of the findings from the skilled persons’ report would be published.
"Nearly a year later, and nearly four years since the report was commissioned, we are still waiting for answers," Morgan wrote. “The report itself is now in the hands of an unknown number of third parties. The FCA now has no control over the timing or content of further public disclosures from it.
“The balance has tipped firmly in favour of full publication. I have written to Mr Bailey to urge him to secure the approval of RBS to do so, without delay.”
Morgan said: "This would not be the first instance of leaking from the FCA, but lessons must be learned to ensure it is the last.”
An FCA spokesperson said: “We have received the TSC’s letter and will respond in due course. We have already initiated a leak inquiry into the disclosure of the s166 report on RBS GRG to the BBC, and we have asked the other parties who had access to the report, namely RBS and Promontory, to do the same.
"If the Treasury Select Committee or the BBC have evidence that the document was leaked by the FCA, we encourage them to share that with us."
RBS is also understood to be investigating the source of leak, which is just the latest of many after successive delays in the publication of the report.
The findings into accusations that RBS purposely pushed small businesses into financial hardship so they could be put into the GRG was first due to be published in 2015. In April, Bailey said it would be published within a year.