Even more troubling is the fact that the overseas funding markets on which banks in this part of the world depend have tightened up on ever-mounting concerns about sovereign debt exposure among European banks.
So far that has had a limited effect on New Zealand banks' cost of funds, in part because of next to no growth in demand for credit over the past couple of years.
"New Zealand and Australian banks are highly liquid," governor Alan Bollard said.
The medium-term funding markets are not particularly healthy at the moment, he said, but the banks had not needed to go to them.
"At some stage they will need to, but that is more a next year story."
The difference between a "mild" impact form international developments, which would see local interest rates rise next year, and a severe one comes down to whether the financial markets on which our banks rely for funding start to jam up as they did after the collapse of Lehmans in 2008.
At the moment looks more like the situation a year earlier when Australasian banks, with virtually no exposer to sub-prime loans, could still access the funds they needed.