A crash in the Auckland housing market is one of the biggest risks to New Zealand's economy over the next few years, Finance Minister Bill English says.

Speaking to a community housing sector conference in Wellington on Friday, Mr English said a fall in house prices would cause problems and he's worried Auckland will follow the same track as "pretty much every other housing market" where prices have gone up year on year.

"That is they stop rising and they come down and people don't like that," he said.

"It creates a lot of problems in an economy and we've seen some economies affected really badly by exactly that phenomenon, Ireland and Spain being two in particular."

Meanwhile, he's also raised concerns about the pressure the government could come under if house prices do keep rising and housing becomes increasingly unaffordable.

"New Zealand governments will come under pressure again to increase all of that income assistance to our low and middle income households, because they just can't pay the bill for their housing," Mr English said.