Jacinda Ardern dampens expectations ahead of first Budget

Prime Minister Jacinda Ardern has issued a warning ahead of the Budget: dampen your expectations, because there are more Middlemores to come.

Ms Ardern said in "almost every portfolio" there are problems caused by "a lack of investment."

"We thought it would be bad. We didn't know it would be this bad," Ms Ardern said at her weekly post-Cabinet press conference.

"We will not be able to address nine years of neglect in one budget."

She said this Budget will be one of "rebuilding" public services.

Middlemore Hospital has become a focus after it was revealed the hospital has mould in the walls.

"The public is seeing just a snapshot of it now," Ms Ardern said. She said there will be examples of issues with service delivery in the lead-up to the election.

It's almost par-for-the-course to lower expectations ahead of the Budget, but not to this extent.

"I had to dampen down [my expectations] when I saw the state that the last Government has left services like health and like education," Ms Ardern said.

But National’s Finance spokesperson Amy Adams says the current Government is lining up its excuses now because it doesn’t want to admit it didn’t get the numbers right.

"There will be things that come up out of the blue. That is quite normal in Government. Under National, we managed that for nine years," she said.

Ms Adams said the National government faced unexpected costs from the likes of several earthquakes and the Rena disaster.

"There will be things that come up out of the blue. That is quite normal in government. Under National, we managed that for nine years.

"We warned their numbers were too tight. They are starting the game of pointing fingers at everyone else."

Finance Minister Grant Robertson has laid out his Budget priorities: critical public services, economic development and supporting the regions, child poverty and homelessness, families and action on environmental challenges.