New Zealand First Leader Winston Peters says National has "thrown older New Zealanders under the bus" by promising to raise the retirement age to 67.
In a statement, Peters – who is also the Deputy Prime Minister – said during coalition talks in 2017, NZ First ensured the age would not be increased during this term of Government.
"The National Party cannot be trusted on superannuation, and their record is littered with broken promises," Peters said.
This morning, National Leader Simon Bridges revealed the party would stick with its pre-election policy of increasing the superannuation age gradually from 65 to 67.
Under National's policy, the increase in superannuation age would increase by six months from 2037.
National stuck to no movement in the super under the eight years of John Key's leadership but changed to age 67 under Bill English's last election.
"We're doing the work now in Opposition so we're ready to hit the ground running in 2020," Bridges said this morning.
Although Peters said National has committed the change would be over 20 years, he questioned if National could be believed when it says it won't happen sooner.
"They increased Labour's superannuation surtax in 1990, after promising to abolish it, no ifs, no buts, no maybes.
"And National were responsible for lowering the New Zealand Superannuation rate from 65 per cent to 60 per cent of the average ordinary time weekly wage."
New Zealand First, he said, is the sole voice in Parliament that has consistently advocated for keeping the Superannuation age at 65.
When in Opposition, Jacinda Ardern had advocated increasing the retirement age to 67.
But speaking at her post-Cabinet press conference today, she said raising the retirement while she is Prime Minister was off the table.
"While I am Prime Minister or while I lead any form of Government I will not increase the retirement age."
"When it comes to the retirement age we have a duty to make sure it's sustainable. And that is why we renewed and re-established contributions to the New Zealand Super Fund that, of course, the last Government stopped."
She said a major concern for the Labour Party had been disproportionately affecting those with shorter life expectancy.