Christopher Luxon is committed to getting the books back to surplus despite saying his government has inherited a "hell of a mess".
It comes after the incoming Prime Minister was given a warning by ratings agency Fitch, urging the National Party to stick to its 2027 surplus promise and avoid any "slippage" that could push the date out further.
Fitch released a note over the weekend giving the finances of the outgoing Labour government the thumbs up but warned the incoming government needs to stick to its promise of delivering a surplus in 2027.
National released its fiscal plan at the end of September, promising to lower debt quicker than Labour and deliver a greater surplus.
The books are currently forecast to return to the black in 2026/27 with a $2.1 billion surplus but under National, it would hit $2.9 billion in that financial year, the party said in its fiscal plan.
Luxon appeared on AM on Wednesday and was asked about the warning from Fitch. He said his government will work hard to keep its promise.
"That's why we released our fiscal plan before the election and that was important. Those numbers we've committed to and that track is what we've locked in," he said.
"We know it's tough because we're actually inheriting a hell of a mess, to be honest with you, and also inheriting some commitments that are made in the first two of those four years, so it's important we understand the reality of what the rating agencies are looking for."
Luxon said the outgoing Labour government committed to a "lot of programs" that weren't fully funded or there were "fiscal cliffs".
But he told AM co-host Ryan Bridge his government is committed to delivering a surplus in 2027.
Luxon also told AM his government is committed to providing a mini-budget in December.
"I think it's important we look to do a mini-budget before Christmas. There is what's called the half-yearly economic fiscal update and I think what we'd do alongside that is have a small number of spending and savings commitments and decisions that we would quickly be getting on with to make sure that's moving in the right direction, then obviously setting up for the major budget in May," he said.
"It'll be small in scale but actually it's just quickly saying right, we think we can make these adjustments now and if we can lock and load those in quickly we'll do that."
It comes as the wait continues for the next government to be formed.
Luxon has consistently said coalition negotiations will happen behind closed doors and not in the media.
National won October's general election with 38.99 percent of the vote compared to 26.85 percent for Labour.
That gave National and the ACT Party a slim majority of 61 seats but might need New Zealand First and Winston Peters if that majority slips after the counting of the special votes, which historically tends to favour the left.
So far, the National leader has only committed to him being Prime Minister and his deputy leader Nicola Willis being his finance minister. Willis is the only person to have had her portfolio confirmed.
Watch the full interview with Christopher Luxon in the video above.
