Thorburn also calls for compulsory KiwiSaver and higher contributions.
There will be consultation with banks in coming weeks on adding details of the policy into its Banking Supervision Handbook.
More respondents in the latest survey feel better off financially than they did a year ago.
The rating agency says persistent current account deficits and a heating property market are threats to the New Zealand economy.
"Most odd. Yes, Heartland is small, but they don't really do home lending."
$60,000 app from Wellington's Paperkite gets a refresh.
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