Public service sector workers are threatening industrial action to get more money because they know the government will help them, Acting Prime Minister Winston Peters says.
Union members at Inland Revenue (IRD) and the Ministry of Business, Innovation and Employment (MBIE) voted "overwhelmingly" to take industrial action on 9 July and 23 July, the Public Service Association (PSA) said.
National Party leader Simon Bridges said the plan showed how the Labour-led government was coping in its new term with 32,000 workers taking part in industrial action in the last nine months, compared with 27,000 in the past nine years.
"This is remarkable in nine months under this government we've seen more strikes, in terms of people out there wanting to do it and doing it, than we saw in nine years under a National-led government," Mr Bridges said.
However, Mr Peters told Morning Report that statement was nonsense.
"Those people involved in industrial action, in this case, is about negotiation," Mr Peters said.
"It demonstrates the naivety of someone who has never known the workforce in the real sense in his whole life."
He said the actions were a result of shortfalls from the previous government but the Labour-led government asked for workers to be patient.
"He [Mr Bridges] says people out there in the workforce expect more from this government, he couldn't be more right. But that's where his correctness stops.
"He's now trying to blow that up to be something egregious and self-centred and wrong.
"We know why people are asking us for more because they know we'll listen and we are prepared to help them, and all we're saying as government is we can't fix up all your neglect for the past nine years in the space of one budget."
PSA national secretary Glenn Barclay said union members were "very reluctant" to take this step on strikes, but felt they had no choice.
"The level of support in the vote shows the level of frustration," he said.
"Spending millions on contractors while denying our members a cost of living pay increase is poor practice, and it's not in the spirit of the new government's expectations for the public sector."
Meanwhile, union members at Inland Revenue have not taken industrial action in more than 20 years.
PSA national secretary Erin Polaczuk said staff were at the end of their tether.
"Our members take their jobs very seriously and they're trying desperately to keep the system on track while Inland Revenue presses ahead with its Business Transformation project which will see one in three staff let go by 2021," she said.