None of Australia's major banks are reviewing their freezes on lending to self-managed super funds after the federal treasurer Josh Frydenberg rejected long-standing recommendations from regulators to legislate a ban.According to a report prepared by the ATO, around A$18 billion worth of SMSF assets in Australia are currently funded by debt following a boom in borrowing activity in the last five years. Most of the borrowings have been used to fund purchases in the residential property market where asset valuations are now under severe pressure.The slide in residential property prices has intensified the reputational risks attending SMSF loans, with many retirement savers now servicing debt on properties in which they hold negative equity.Only a handful of second tier banks continue to target SMSF borrowers amid deepening industry concerns that such lending might not be consistent with the requirements of responsible lending laws.They include Bank of Queensland, IMB and Hume Bank, along with non-bank lenders such as Liberty Financial.However, the federal government's decision does not appear to have inspired a rethink at any of the major banks.Westpac, which ditched its SMSF credit products last July, said yesterday it had no intention of reviewing its decision to exit the market segment."Westpac definitely has no plans to reintroduce lending in this area," a spokesman said.Feedback from CBA and ANZ sources indicates that neither is contemplating a re-entry into SMSF lending.While ANZ has been out of SMSF lending for at least four years, CBA withdraw from the market last October saying that it wanted to "simply and streamline" its lending strategy.NAB was the last of the majors to rein in lending to super funds, after it announced in February that it would not lend to clients with net superannuation assets of less than $5 million.The tightened eligibility criteria for NAB customers will take effect at the end of this week.A NAB source said the government's decision not to introduce a ban would have no impact on its decision to wind down its exposure to SMSF borrowers.David Murray's 2015 financial system inquiry recommended a blanket ban on borrowing by superannuation funds, but the proposal was not implemented by the then Turnbull government.The Labor opposition has announced it would end the practice if it wins the federal election this year.