VIENNA, Nov 22 Reuters Austria should keep its recently introduced compulsory standards for mortgage lending, the Austrian National Bank ONB said on Tuesday, despite a recent call by the conservative finance minister for those standards to be reviewed.

Faced with a sustained housing boom and banks39; widespread flouting of recommendations on mortgage lending aimed at limiting risk, Austria introduced the compulsory standards in August, though banks are still allowed to deviate from them in up to 20 of cases.

They include capping loantovalue ratios at 90, limiting maturities to 35 years and imposing a maximum debt service ratio of 40. With interest rates now rising, however, Finance Minister Magnus Brunner has asked that the decision to introduce the compulsory standards be reviewed to make lending easier.

The newly adopted regulation contributes to safeguarding financial stability by curbing excessive developments in residential real estate lending, the ONB said in a statement on its semiannual Financial Stability Report, referring to the binding standards.

The regulation introducing those standards was issued by the Financial Market Authority FMA, though the standards were developed by the Financial Market Stability Board, which brings together officials from the Finance Ministry, ONB and FMA.

Banking supervision is shared between the FMA and ONB the FMA is responsible for banking supervision proper while the ONB is in charge of financial stability as a whole and…