The Government is being challenged to use the information it will soon start collecting on property purchases to set up a register of foreign buyers.
From October, the Government will begin collecting bank and tax details of people buying investment properties, including those from overseas.
It said the data will bolster tax collected on property sales, but Treasury said it would also create a more accurate picture of foreign ownership of housing.
The Labour Party says house prices in Auckland are soaring and the public has a right to know whether foreign buyers are fuelling the market.
Labour's housing spokesperson Phil Twyford said until now the Government had refused to collect the statistics that would reveal the scale of foreign ownership of New Zealand's homes.
He said people simply did not know to what degree foreign owners were fuelling the Auckland housing crisis.
Mr Twyford said it was critical that the Government now used the data to create a register.
"I challenge them to promise that they will use that information that was gathered through Inland Revenue to establish a register of foreign ownership of New Zealand residential real estate.
"And then to put the facts on the table and tell New Zealanders exactly what's going on," Mr Twyford said.
New Zealand First housing spokesperson Denis O'Rourke said his party had been calling for a register for foreign buyers of residential and rural land for years.
He said identifying home buyers via tax information was a step in the right direction because at the moment New Zealand had no good data at all.
"We have no information at all, and if the information is going to be gathered then why shouldn't it be public?
"We all want to know about this, we all want to see the statistics and work it out for ourselves," Mr O'Rourke said.
However, Housing Minister Nick Smith said while the tax and bank data the Government will begin collecting would give it a better picture of foreign ownership of houses in New Zealand, there was no need for a register of foreign owners.
He said numerous Government departments told him foreign buyers were not having any significant effect on the Auckland housing market.
Documents released by Treasury this week reveal that it does not believe foreign ownership is a particular problem.
Its best guess is that three percent of New Zealand's homes fall into this category.
However, Land Information New Zealand said there was no comprehensive source of data to support or contradict any claims about foreign ownership of housing in New Zealand.