Watch: Jacinda Ardern makes first pre-Budget reveal - Govt to spend $6m to fix bungled Census

Prime Minister Jacinda Ardern has made her first pre-Budget funding announcement, saying the Government spend almost $6 million to fix issues with the Census.

Ardern, along with Minister of Statistics James Shaw, also announced during today's post-Cabinet press conference that $10m would be provided to enable Stats NZ to get ahead of the next Census.

The previous National-led Government decided to shift the Census to a mostly online survey and, at the same time, directed Stats NZ to cut costs over two census cycles," Shaw said.

"Stats NZ has now confirmed it will provide reliable, quality 2018 census data to calculate how many electorates will be needed for next year's General Election and to revise electorate boundaries where necessary," Shaw said.

"It had to delay other work and re-allocate funds to do it. As a result there's a shortfall of $5.76m needed to complete the delayed work, and that's being covered in this year's Budget," Shaw said.

"There's also Budget approval this year of $10.36m to enable Stats NZ to get ahead of the next census. The money will develop the business case for the 2023 Census and start development work on it.

"That development work will incorporate any improvements that are recommended by experts who have been reviewing issues with the 2018 Census," Shaw said.

Stats NZ has now confirmed it will provide reliable, quality 2018 census data to calculate how many electorates will be needed for next year's General Election and to revise electorate boundaries where necessary, Shaw said.

Shaw said Stats NZ has "made do" with the fund it had, but the funding increase would help Stats with the survey.

Shaw assured media that "no one would be left out" as a result of the lower than expected turn out in the 2018 Census.

Shaw said the 2018 was not a botched job.

"The most important information was still going to be available, at least in the same quality we have had in the past."

Shaw said he would be "reserving his judgment" about how the Census was executed until the independent review is completed in July.

He said he was "hot under the collar" about the way National have been slamming the way the Census has been rolled out.

Ardern is also expected to face questions during the press conference about the devastating head-on collision between an SUV and a van on State Highway 1 near Ohakuri Rd, Atiamuri, yesterday morning.

The driver of an SUV and the driver and six passengers in the van were killed.

A 9-year-old boy was rushed to Waikato Hospital in a critical condition via helicopter from Tokoroa Hospital. He is now stable in a ward, a hospital spokeswoman said.

Clive Matthew-Wilson, editor of car review website Dog & Lemon said the Government had "blood on its hands" over the incident.

"Eight people are dead because a simple barrier was missing off the centre of the road," he told the Herald. "That's the simple fact.

"If the Government is serious about lowering the road toll, the highest priority must be given to improving the safety of our third world roads."

Ardern is expected to face questions about the Government's commitment to road safety.

She is also expected to face questions over the unveiling of the data from the 2018 Census.

This morning, the Government's chief statistician Liz MacPherson said Stats NZ would begin rolling out the results of the census in September this year.

But she also said that because of lower than expected turnout, the Stats NZ had to fill the gaps in the data with other Government information.