The National Party is threatening to torpedo any Government plan to merge Radio NZ and TVNZ if elected this year.
Cabinet ministers this week agreed to proceed and commission a business case to combine the two state broadcasters into one giant entity, potentially by about 2023, according to RNZ.
The decision comes after Broadcasting Minister Kris Faafoi's original plan - to pass legislation under urgency to disestablished TVNZ and RNZ, and look at a business case this year – was rejected by Cabinet last year.
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Faafoi has declined to discuss the plan but deputy Prime Minister Winston Peters on Wednesday confirmed the Government was now looking to put together a business case.
"Our preference is for competition, but sustainable competition," Peters said.
"Something's got to be done. We cannot just stand by in all these new circumstances with the media fighting for their lives against international competition."
National's broadcasting spokeswoman, Melissa Lee, said while getting the business case together first and slowing the process down made sense, there were still serious concerns.
"We are against any big mega giant merger of two entities that will become so big they will basically eat the other media outfits up," Lee said.
"We always wanted plurality of voice in the media landscape and if anything was to change the plurality we would need to understand why … If it's a good idea we would probably support it but they still haven't put the case to us and as far as I'm concerned, reducing plurality is never a good idea."
Lee said if any decision was made before September's general election, National would potentially reverse it if it regained power.
"I'm not sure when National becomes government if we can guarantee to continue the plan," she said.
"If they decide to merge RNZ and TVNZ I am not sure we will continue down that path. I think it would be rushing it."
Opposition Leader Simon Bridges, too, said his party would reject a merger.
He said combining the two organisation would be "monolithic," and that a state-owned media entity of that size would crowd out other publications.
"TVNZ and RNZ together would be very big and very powerful – a merger would be a bad solution."
The Government has been trying to figure out a solution to help public broadcasters since a Labour pledge to create an upgraded Radio NZ with $38 million was canned after the resignation of former Broadcast Minister Clare Curran.