The government is at loggerheads with Auckland Council over how much land is available to build on in the city, as debate over housing affordability heats up.
Finance Minister Bill English says the government is working with the council and developers to get to the bottom of the land availability issues the government says are to blame for high house prices.
"The prices in Auckland tell us that there's probably a shortage, regardless of what the (local) politicians think," he told Radio New Zealand.
"House prices in Auckland are going up and that tells us that demand is exceeding supply, and we want to increase the supply.
"When we know what the number really is, got a sound basis for it, both the council and the government have got the opportunity to improve the supply of building opportunities, so we don't have a market bubble."
Auckland Mayor Len Brown disputes that a shortage of land is to blame for house prices, and says 15,000 sections are available to be built on straight away, in areas like Flat Bush, Riverhead, Takanini and Hobsonville.
He says roads and infrastructure are available for those sections to be built on.
"We've been saying that figure or there-about for the last 12 or 18 months, and what is critical to understand is that the reason that house prices are now starting to move in Auckland is the Auckland property market is starting to move (after the recession)," he says.
"It's a hot market ... people are building flat out and buying flat out."
He says the council also has applications to build thousands of inner-city developments, while a lot of greenfields land is already in developers' hands.
Mr Brown agrees with the government that changes to ensure land can be released more quickly are necessary.
The government plans to amend the Resource Management Act to streamline Auckland's unitary plan and consenting decisions.