New Zealand First Minister Shane Jones wants politicians to have more influence over public servants, saying there is a need for a "dose of reform at the very top".
But the Public Service Association, which represents workers in the sector, has warned any moves to politicise the public service will be "strongly opposed".
State sector employees are legally required to be politically neutral at work so they can maintain the public's trust and implement the policies of current and future governments.
But the Regional Development Minister says there's a problem with "bureaucratic culture" and "red tape".
"I'm astounded how long it takes things like building a new road or bridge or infrastructure projects, how long it takes to get things up and running in New Zealand," he told RNZ on Thursday.
Mr Jones wants ministers to be able to appoint people to senior roles in the public service, but hasn't said which positions he has in mind.
He said he'll be taking his ideas to the New Zealand First party conference later this year.
PSA national secretaries Erin Polaczuk and Glenn Barclay said Mr Jones' view of the public service "is outdated, out of touch and - frankly - out of order".
They said it would undermine the public service in its ability to be "free, frank and fearless" rather than "controlled, cowed and cronyistic".
"New Zealand is rated at the very top of Transparency International's list of the least corrupt countries in the world," they said in a statement.
"Cronyism and political interference would severely damage that reputation."
They said if Mr Jones was concerned about delays, he should instead lift the cap on public service staffing and push for the Government to relax its budget responsibility rules.
National regional development spokesperson Paul Goldsmith said Mr Jones is simply trying to remove any restraints for himself to allocate funding as he sees fit.
"Mr Jones is determined to shovel $3 billion of taxpayers' precious money out the door as fast as possible. Anybody that troubles him with due process and asking pesky questions like ‘what are getting for this money?’ is abused," Mr Goldsmith said.
He said while the politically neutral public service can be frustrating, they are there "to ensure taxpayers' money isn't wasted and everyone is treated fairly".