Housing Minister Nick Smith says thousands of new homes will be built as part of a planned affordable housing development on vacant Crown land.
The Government is planning to develop 430ha of vacant land in Auckland controlled by various government agencies.
Speaking ahead of this afternoon's Budget announcement, Dr Smith told Radio New Zealand this morning that it was too early to speculate on how many houses would be built.
However, he said the number would probably be in the thousands -- a similar scale to developments at Hobsonville Point and Weymouth.
"Quite clearly the Government's objective is increasing supply, doing so quickly and trying to get more homes in Auckland," he said.
There were issues of first right of refusal constraints that would need to be worked through with local iwi, as the developments would be on Crown land.
"With Weymouth, we've actually chosen to partner with local iwi as part of those housing developments," he said.
"I would expect there may be some initiatives like that that will flow from this."
The minister described Tamaki as being "real confused network of underutilised land" and defended plans to build on public reserves.
"The public impression when you say the word reserve is a wonderful park that's being well utilised," he told Radio New Zealand.
"We've got areas of Auckland that are local purposes reserve that haven't had anybody play on them or use them for any recreational purpose for more than a decade."
Dr Smith added: "We're specifically wanting to identify developers who are able to produce more affordable product at scale.
"It is not until we get those bidders come in that we'll be able to get a good idea of where housing developments on this land will be financially viable."
Labour's housing spokesperson Phil Twyford said National had simply dusted off Labour's 2008 inventory of government land available for housing and re-announced it.
"Despite National ridiculing this at the time, it is a no-brainer to develop vacant government land in Auckland," he said.
"The Government should have continued Labour's work in this area seven years ago. If it had, we would have had thousands of new homes and the housing crisis might not be as bad."
The Government had been a bystander during the housing crisis, Mr Twyford said, and the freeing up of vacant government land was part of a "poll-driven pre-Budget panic."
Any move to free up Crown land for Auckland housing must come with a guarantee of 100 per cent affordable housing, the Green Party said.
"The Government can't fix the housing crisis in Auckland by freeing up large swathes of land so developers can then build houses that Aucklanders can't actually afford to buy," Green Party co-leader Metiria Turei said.