The Finance Minister has reportedly met with public service bosses to discuss options to cut back on spending.
It comes after NZ First leader and former deputy Prime Minister Winston Peters on Wednesday claimed there was a $20 billion hole in the Government's revenue - a claim Finance Minister Grant Robertson denied.
However, the NZ Herald is reporting Robertson met with public service bosses "as recently as" Wednesday - during which discussions were held about restraint on spending.
National's deputy leader and finance spokesperson Nicola Willis said such meetings were "too little too late".
"I liken it to a situation where you've had a house that's on fire… and now, after two years of burning, the Finance Minister is reaching for the hose? I mean, for goodness sake," Willis told AM.
"We've been saying for years, 'The spending's out of control, bring some discipline in' - and I think this is a last-minute hail mary."
ACT Party leader David Seymour, in a statement on Wednesday, said Labour was "in a sad and desperate state, attempting to make these savings just weeks before an election".
Last month, the Government's financial books showed its tax take was falling sharply - with businesses being hit hard by higher costs and lower profits.
"The Government took $2.329 billion less revenue in the 11 months to May than Treasury had forecast as recently as the Budget Economic and Fiscal Update, which was released on May 18," Seymour said.
"Labour has increased Government spending by $56 billion over six budgets and some of the spending is so damaging it must be stopped on day one of the next Government."
In the 11 months to May, New Zealand recorded a total deficit (operating balance before gains and losses) of $6.5b - more than $2b than projected in May's Budget but $1b lower than in 2022.
At the time, Robertson said the Government "had already taken steps to respond to the uncertain economic environment by carefully and responsibly managing its spending".