Any dilution of the RDR proposals will increase costs on consumers through continued mis-selling, the FSA warns today in a letter to the Treasury Select Committee (TSC).
The letter addressed to chairman Andrew Tyrie from FSA chief executive Hector Sants also states the RDR "will not threaten the availability of good advice" post 2012.
It comes in response to the TSC's call for written evidence on the RDR last month.
The regulator will submit formal evidence to the Committee before its 27 January deadline, but says in the meantime it wanted to outline why it remains "committed to modernising the industry through RDR".
It follows a House of Commons debate on the Review last month, which centred on the regulator's proposals for increased qualifications for advisers.
"We are of course aware of the concern that has been voiced in recent weeks by individual advisers and some of your parliamentary colleagues about the impact the RDR, and in particular our professionalism proposals, may have on this sector," the letter states.
"We do not agree that the RDR will threaten the availability of good quality advice."
The letter says if consumers are being advised on how to invest their life savings, they would "expect an adviser to be professional and for that professionalism to be closer to the standards of a lawyer or accountant. At present this is not the case."
Existing advisers will have had four years to prepare for the RDR by the time it is introduced in January 2013, it states.
On grandfathering, the FSA says its experience in allowing grandfathering rights for mortgage brokers has been that it has seen "a continuation of mis-selling", resulting in about 100 broker disqualifications.
Under a heading 'Problems in the market', the regulator says mis-selling scandals in the retail investment market are responsible for an estimated annual consumer detriment of £223m.
"This is not just a historic issue", it states. "Our supervision has shown that problems continue to exist in the market and there is widespread agreement that fundamental changes are needed."
"Any dilution of the proposals will result in an increase in the cost to consumers through continued mis-selling."
The TSC called for written evidence on the RDR in November. It has invited stakeholders to comment on whether they believe the Review will achieve its stated outcomes.
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