National's under growing pressure to re-think its stance on the retirement age following a report warning of a pending crisis.
The Financial Services Council says Kiwis are living longer and tax rates will need to rise by almost a third later this century to continue funding super at 65.
It says around half those born last year are expected to make it to 100.
Labour leader David Shearer is urging immediate action, saying in just three years the superannuation bill will be bigger than the entire education bill:
Mr Shearer is keen to enter cross-party talks with National on the issue, saying the age of eligibility should go up and Kiwisaver should be compulsory.
Mr Key famously swore he would resign if he broke his promise not to increase the retirement age.
RadioLIVE / 3 News