The FCA began a review into responsible lending this month, a year after the MMR came into effect.
A spokesman for the City watchdog said the regulator aimed to finish the review later this year.
The FCA has also announced it will begin a wider assessment of barriers to competition in the mortgage market in the autumn.
Last year, Linda Woodall, director of mortgage and consumer lending, claimed it had been “business as usual” for the mortgage industry nine months into the new MMR regime.
Ms Woodall said: “Despite numerous headlines about intrusive income and expenditure checks it has, in the main, been very much business as usual for most firms.
“Lenders have carried on lending and consumers are still getting mortgages.”
She hinted that those seeking interest-only mortgages, the self-employed, those who previously needed to self-certify their incomes and those with a bad credit record. could be hit by the changes.
According to the FCA, there had been a downward trend in lending to these groups since 2008.
Adviser view
Chris Taylor, director of London-based the London Mortgage Brokers, said: “I agree that the mortgage market has been business as usual. Interest-only mortgages have declined but I do not know if that has been because of the MMR specifically. Generally, some buyers have found it hard to get a mortgage because of the high income multiples.”
