AIFA says the FSA has yet to explain a dramatic 37,000 drop in the estimated number of UK advisers.
In a consultation paper on professionalism published last month, the FSA said it monitors about 48,000 individual investment advisers currently approved to offer advice in the retail market.
But in a consultation paper published in June 2009, the regulator said it estimated RDR costs based on a population of 60,000 advisers. It also acknowledged there may be as many as 85,000 advisers registered.
After the publication of the June 2010 paper, AIFA said the "unexplained" reduction in adviser numbers represented a "cause for concern" and deserved immediate clarification by the FSA.
But AIFA policy director Andrew Strange says the regulator has yet to explain the drop.
"We will be publicly seeking further clarification on this," he says. "It is an important issue and one I have not yet received a satisfactory response to.
"It is such a huge drop in adviser numbers without an explanation. However, AIFA is aware that, until the final RDR rules are established, there are a number of people unsure what their role will be after 2012."
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