The Government is ramping up its attack on Labour's housing policy, saying the party is dreaming if it thinks it can meet its home building targets.
Party leader Andrew Little announced on Sunday that under a Labour-led Government, a new Affordable Housing Authority would fast-track the building of more affordable homes.
It would be the driving force behind Labour's updated KiwiBuild programme, which aims to build 100,000 affordable homes over 10 years - 50,000 of them in Auckland.
The KiwiBuild homes would be financed by an initial $2 billion from the government.
As the houses were sold, the money would be re-invested to build more.
Economic Development Minister Steven Joyce says he's crunched the numbers and the targets are "simply fanciful".
"The $2 billion they're allocating is enough money, by their own calculations, to build 4000 at around $500,000 per house," he said on Monday.
"They would have to buy the land, get the consents, build the infrastructure, design 4000 houses, build 4000 houses and sell 4000 houses all in five months - not just once but 25 times.
"Tell 'em they're dreaming."
Mr Joyce says Labour would be caught by the same planning and infrastructure delays affecting all developers.
"The Government's comprehensive housing plan is building 85,000 houses over this term of parliament," he said.
"The only difference is we don't have Labour's magic pixie dust to turn 4000 houses into 100,000 - sadly for them, I don't think they do either."
Meanwhile, United Future leader Peter Dunne has taken a shot at both parties.
"Over the past week we have seen an abundance of essentially scatter-gun policies proposed," he said.
"National says Labour is copying its policies and then, curiously, that it will not work.
"And Labour announces a so-called affordable housing package without any indication of how young families will be financed into these homes.
"It all sounds like the Mad Hatter's Tea Party."