Reserve Bank Governor Alan Bollard has called on banks to say whether or not they'll join a new scheme guaranteeing customers' deposits.
All of the banks are currently part of the Government's scheme guaranteeing customers deposits up until October this year.
Several banks say they probably won't join a replacement scheme that runs until the end of 2011 but no banks have made formal decisions.
A Massey University banking expert, Claire Matthews, says banks have to pay large fees to the Government's extended scheme.
She says pressure could come on them to pass on the savings they would make by not participating in the scheme to depositors.
Commitment to scheme being 'fudged'
Dr Bollard says the banks don't need the guarantee and is calling on them to be upfront with customers over their intentions.
Radio New Zealand's economics correspondent says critics say banks are fudging committing to the scheme in order to avoid paying higher interest rates on deposits that will no longer be covered by the existing guarantee.
The Finsec union says savings should be passed on to depositors in the form of higher interest rates if banks are going to opt out.
To date, the Government has collected $200 million in fees from financial institutions participating in the scheme.
