Minister David Parker has released a timeline of the attempts from the Government Communications Security Bureau to warn the Beehive against depicting the access of Budget 2019 information as a systematic hack.
National leader Simon Bridges has called on the Government to "come clean" about when they knew about the GCSB warning and why they didn't immediately reveal what the GCSB had said.
He said senior Ministers had deliberately left the false impression that the National Party had hacked the Treasury, but Prime Minister Jacinda Ardern has pushed back, saying that no one was accusing the National Party of anything.
On Tuesday May 28, the GCSB tried to contact GCSB Minister Andrew Little to say it believed that no hacking of the Treasury had taken place.
Earlier that day, the National Party had released a trickle of Budget information two days before Budget day.
That Tuesday evening, Treasury boss Gabriel Makhlouf and Finance Minister Grant Robertson released statements saying that the Treasury had been systematically hacked , and that the police had been called in.
Ardern has given different timelines of when the GCSB information came to the Beehive, but Parker today clarified matters during Question Time.
Parker, who is acting GCSB Minister while Andrew Little is overseas, said the GCSB contacted Little's office at 8.43pm on Tuesday May 28.
That was about 40 minutes after Makhlouf publicly said that his department had been hacked, and about 30 minutes after Robertson echoed Makhlouf's description and linked it to the Budget material the National Party had obtained.
Ardern told the House that Little did not answer the 8.43pm call because he was in a meeting, but the GCSB also contacted the head of the Department of Prime Minister and Cabinet at about the same time, and she was notified soon afterwards.
Parker said that Little didn't actually speak to the GCSB until 9.43pm, and he then immediately tried to call Robertson. After not receiving an answer, Little contacted Ardern's office, and he eventually sent Robertson a text message at 10.25pm that night.
Parker rejected that there had been any delay in passing on the GCSB information.
"There wasn't a delay of hours. Immediately upon the conversation between Minister Little and GCSB, he put a call into Minister Robertson," he told the House.
"Minister Robertson was not available and did not pick up, so Minister Little immediately contacted the Prime Minister's office and spoke to the Prime Minister's deputy chief of staff."
Ardern said during Question Time that the GCSB told Ministers that what had happened to the Treasury was "unauthorised access".
She defended the original description of what happened as systematic hacking, saying "that was the information that we had" at the time.
Bridges said that Ministers had allowed a "fundamental mistruth" to permeate the following day by not revealing the GCSB advice, but Ardern rejected that.
She said Ministers changed their language according to the GCSB advice, and they still did not know whether anything illegal had happened and wanted to let the police do their job.
She said she was told about police advice that nothing illegal had happened on the following evening on May 29, and the Treasury released a statement revealing that police advice the following morning, May 30, at 5am.
Bridges has called for Deputy Prime Minister Winston Peters to apologise for saying that the National Party had acted illegally, but Peters again stood by his previous comments today.
Peters added that he believed National had engaged in "hacking" and, during Question Time, he referred to a section of the Crimes Act about intentionally accessing a computer system without authorisation.
The State Services Commission is conducting an investigation into whether Makhlouf misled the Government.
It is also doing a separate inquiry into how sensitive information on the Treasury's website wasn't secure.
Today the commission announced that Murray Jack would head that inquiry, and it would look at what happened, why it happened, the lessons learned, and the actions the Treasury needed to take to prevent it happening again.
Jack is a professional director, Chair of Chartered Accountants Australia and New Zealand and a former member of the board of the Financial Markets Authority. He was previously chairman and chief executive of Deloitte NZ.