Jacinda Ardern dodges questions about Treasury's bungling of Budget information

Prime Minister Jacinda Ardern and Treasury Secretary Gabriel Makhlouf are batting away questions about Treasury's mishandling of Budget 2019 information, which National Party staffers accessed earlier this week by simply searching Treasury's website.

National Party leader Simon Bridges is calling for Makhlouf to resign after "smearing" the party by saying the information had been hacked from the Treasury website and asking police to investigate.

But police said that nothing illegal appeared to have taken place, Treasury said this morning.

Bridges said Robertson should also resign for backing Treasury, and Deputy Prime Minister Winston Peters should apologise for saying that National had acted illegally.

The State Services Commission is now investigating.

"Treasury has known since Tuesday exactly what happened and they covered it up to hide their incompetence," Bridges said this morning.

"They have sat on a lie, calling the National Party criminal hackers and calling in the police."

He said Robertson was "donkey deep" in this.

"He does not have the moral authority to deliver the Government's Budget today."

Robertson said today that he was "very disappointed" that Treasury did not seek more information before referring the matter to police.

But it is understood that he had no intention of resigning.

He had also not spoken to Makhlouf about whether Makhlouf would resign.

"I've been focusing on delivering this Budget," Robertson said.

Makhlouf refused to answer questions.

Ardern said she had not asked for Makhlouf's resignation, and repeatedly answered questions about him by saying she was focused on delivering the Budget.

She did not expect Robertson to resign, saying she was proud of him for today's Budget, and she had confidence in the Treasury.

Peters stood by his previous comments about National acting illegally.

"There are lawyers, and I'm one, that think that sort of behaviour is a crime.

"If you think the go-to place for legal opinions and judgments are police and not lawyers, then you're a bit misguided."

He said a staffer in National MP Chris Bishop's office had accessed the Treasury information, and he should have known not to do that.

"Everyone knows the Budget should be secret ... To say 'we simply did this and we struck oil' doesn't forgive him for doing it."

Bishop declined to comment.

National had released Budget information earlier this week, forcing the Government onto the defensive.

Bridges said accessing the information was akin to grabbing items in the street that had a sign on them saying "free to a good home".

"Any member of the NZ public could have done this if they had an interest in the Budget, from your grandson to your grandma.

"The Deputy Prime Minister of New Zealand came out and accused me of criminal behaviour. That is disgraceful."

Bridges has previously said that Robertson had implied that National had hacked the Treasury, which had tainted National with an accusation that was wrong.

Robertson and Ardern have repeatedly tried to distance the Government from any implication that National had hacked the Treasury website.