Green MP Sue Kedgley has accused the Government of starving Radio New Zealand of money in an attempt to threaten its viability.
The future of the public broadcaster has come under question after the release of documents detailing Broadcasting Minister Jonathan Coleman's concerns about whether Radio New Zealand is doing enough to live within its means.
Radio New Zealand appeared before Parliament's commerce select committee on Thursday morning for its annual financial review.
However, the hearing was dominated by questioning over whether the broadcaster could meet its charter obligations, given that its funding has now been frozen.
The hearing became heated when Ms Kedgley suggested that the National Government was starving Radio New Zealand of money.
National MPs objected to her line of questioning, saying the broadcaster's funding had not been cut, but simply frozen.
But on her way into Parliament on Thursday afternoon, Ms Kedgley said National's approach was purely political.
"There is political interference by the minister in the internal operations of Radio New Zealand. I think the minister has a conscious policy of trying to starve Radio New Zealand, so that it will ultimately become unviable as a public service broadcaster."
Board chair plays down reports of rift
Radio New Zealand chair Christine Grice played down reports of a rift between the board and Dr Coleman.
Ms Grice appeared before the select committee on Thursday morning and was questioned about reports that the board was at odds with the minister over the decision to freeze funding.
She was repeatedly asked whether she felt bullied by Dr Coleman, but told the select committee that the board is well aware of its responsibilities.
Ms Grice also confirmed the board is considering a range of options to save money, including turning off Radio New Zealand National between midnight and 6am and broadcasting to some parts of the country on AM rather than FM.
Ms Grice refused to answer directly questions about whether she thought cuts could lead to a "dumbing down" of the service.
But Radio New Zealand chief executive Peter Cavanagh said that, inevitably, quality would decline as funding got tighter.
RNZ directed to find ways of cutting costs
Radio New Zealand has been asked by the Government to find ways to cut costs and has been told any increase in funding in the foreseeable future is unlikely.
Board members have been told that if they do not believe they can achieve that, they may be replaced with people who can.
Broadcasting Minister Jonathan Coleman has asked the board to consider alternative revenue models and options for reconfiguring services.
He says options such as commercial sponsorship for Radio New Zealand Concert, reviewing the size of the Auckland operation and generating new sources of revenue will have to be explored.
Dr Coleman told Morning Report this may require a change of mindset from board members and senior management.
"I'm not directing them what options to choose, but I certainly want them to thoroughly examine the range of options and finally adopting some of those options is going to actually entail a change of mindset."
In response, the board says Radio New Zealand has already made operational cuts and programming changes, and any further reductions would result in what it says would be a "dumbing down" of its service.