Grant Robertson has rejected calls for his resignation, saying he has been focussed on delivering the budget not his job.
The Finance Minister appeared on the Newshub Nation Budget Special just minutes after delivering the 2019 Well Being Budget.
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Host Simon Shepherd asked Robertson if he was happy with his handling of the National Party leaking parts of the budget and Simon Bridges calling for his resignation.
"I completely reject that, my focus has been on delivering this budget today. I think what New Zealanders care about are the programmes we have got in this budget, the fact we are taking these issues seriously.
"That is what they have wanted me to focus on and that is what we have been doing."
Earlier on Thursday Bridges said the country has witnessed the most contemptible behaviour by a government.
"It shows a bungling incompetence, and how this Government reacts under pressure, and that is deeply dishonestly and bringing smears against the opposition."
Bridges then called for Robertson's resignation saying he did not have the moral authority to deliver the Government's budget.
The calls for the Finance Minister to resign were the latest in a tumultuous week of accusations between the two political parties.
On Tuesday, Bridges revealed details of the Wellbeing Budget - two days before the official announcement. Robertson admitted some of the information was correct.
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.
Treasury head Gabriel Makhlouf said there had been 2000 attempts at attacking the Treasury's system in 48 hours.
But on Thursday, Treasury released a statement saying that they had been advised by police that, on available information, it appeared someone had "exploited a feature in the website search tool", which "does not appear to be unlawful".
Treasury said that as part of its preparation for the Budget, it had developed a clone of its website and Budget information was added to the cloned website "as and when each Budget document was finalised".
"On Budget Day, the Treasury intended to swap the clone website to the live website so that the Budget 2019 information was available online".
But the clone website had not been publicly accessible, according to Treasury.
The statement said as a result, a specifically-worded search would be able to surface "small amounts of content from the 2019/20 Estimates documents".