The Reserve Bank won't impose new lending restrictions for highly-leveraged investment purchases until the start of October, giving lenders an extra month to clear their backlog of pre-approvals.
The central bank plans to extend mortgage lending restrictions on Auckland property investors to the rest of the country, making them more onerous by requiring a bigger deposit and reintroducing a uniform national cap on highly leveraged owner-occupier mortgages.
The proposed changes, originally due to be introduced in September, would cap property investor loans with less than 40 percent as a deposit to just 5 percent of lending and restrict owner-occupiers with less than a fifth down to 10 percent.
The major banks responded by adopting the new rules early, something the RBNZ acknowledged in giving them leeway before the new rules are formally introduced.
"Banks have indicated through their submissions that more time is required to enable them to meet the new restrictions that apply to investor loans nationwide, given the pipeline of loan pre-approvals made prior to our announcement in July," deputy governor Grant Spencer said in a statement.
Mr Spencer said the bank is still analysing submissions on the proposals and may make further adjustments.
A final position is expected to be released later this month, he said.
The Reserve Bank expects the even tougher restrictions on highly-levered mortgages will curb some of the "excessive" house price inflation, but has consistently said a shortage of supply needs to be addressed before any meaningful difference can be made.
The central bank cut the official cash rate to a new record low of 2 percent on Thursday, though ANZ, Westpac and BNZ only passed on some of the reduction to floating mortgages while at the same time raising their deposit rates.
Governor Graeme Wheeler on Thursday said the bank was still looking at adding debt-to-income ratio to its macro-prudential tool-kit.
He said he expected to see Finance Minister Bill English in the next week or two to request adding it to the central bank's memorandum of understanding with the government.