The actions of the National Party in releasing unauthorised Budget details have been labelled "phenomenal" and sparking the fuse of a "political rollercoaster".
On Tuesday, National leader Simon Bridges revealed details of the Wellbeing Budget - two days before the official announcement. Finance Minister Grant Robertson admitted some of the information was correct.
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Later that evening, Treasury, which has access to Budget information, released a statement saying there was sufficient evidence to show its systems had been deliberately and systematically hacked.
It referred the issue to the police on the advice from the National Cyber Security Centre and Robertson called on the National Party to not leak any more information.
"We have contacted the National Party tonight to request that they do not release any further material, given that the Treasury said they have sufficient evidence that indicates the material is a result of a systematic hack and is now subject to a Police investigation."
Bridges reacted to that by saying Robertson was smearing the National Party and when "what has occurred is revealed, he will need to resign".
Tuesday's events lit a fuse on what Newshub's Political Editor Tova O'Brien described as "probably the biggest political scandal of 2019" and a "political rollercoaster".
"From the outset, the fact that details of the Budget were being released by the Finance Minister's enemies in the National Party, that was huge and exceptional," she told The AM Show on Wednesday.
She said the Treasury's announcement on Tuesday evening that there was evidence of hacking was "phenomenal"
"This is war between the Finance Minister and the National Party. It's huge. All of these things are massive."
O'Brien made reference to how rare it is for Budget details to be made public before the Finance Minister decides it is appropriate, noting the only two recent examples were in 2006 and 1986.
In 1986, when Budget details were released pre-Budget, then-Finance Minister Roger Douglas offered his resignation.
She said the hack put Bridges, Robertson and the Treasury all in a difficult situation, but said there was also the matter of ensuring any issues with Treasury's security were fixed.
"If the Treasury has indeed been hacked, in the way that it is suggesting, hello Russia and China, come on in.
"What else are people able to get their hands on?"
Political commentator Chris Trotter told The AM Show that if he had got his hands on information, he would have done everything to ensure pressure was placed on the Government to explain why it had got out.
"What I probably would have tried to do is first of all tell the Government 'you've got a leak, I am getting information, this is a very serious breach of security' and somehow allow people like yourself Duncan to know that there had been a leak.'
"Then all the pressure would have come on the Government… but no fingerprints for the National Party."
But he said the hack changed the story.
"[The budget details getting out] is very embarrassing for the Government, but the hack news has come as a sort of a lifesaver," he said.
Later on Wednesday, Bridges said he knew where the information had come from - and it wasn't from a hack.
"We have acted legally, appropriately, without any hacking or anything approaching that by the National Party."
The Treasury says there had been at least 2000 attempts to attack its systems, but it was currently unaware of if the hacks had come from New Zealand or from overseas.