Green Party leader Eamon Ryan has accused the Government of "throttling" RTÉ in terms of its funding.
Earlier this month, RTÉ Director General Dee Forbes told staff the organisation's current financial situation is unlike anything it had seen before and it was reassessing everything it did.
In a note to staff, Ms Forbes said the decision to defer implementation of a revised media charge meant a crisis in the funding of public service media would continue.
Today, Mr Ryan said: "This Government's throttling of RTÉ with the ongoing decline in their funding model and the refusal of the Government to accept the recommendations that our own committee made for funding RTÉ and other Irish media properly is deeply worrying."
Mr Ryan said the issue of disinformation and fake news was troubling countries across the world and putting democracies under threat.
"Clearly one of the responses to that is a strong media that can tell the difference between what is fake and what is real, and can tell our people with real clarity and honesty and independence what is happening in the world," he told the Dáil.
"We are now facing the prospect of the closure of RTÉ in Cork or the closure of Lyric FM or the sale of more land in RTÉ as they continue to sell capital assets to cover current expenditure."
"When is the Government going to change its position of trying to kill that media sector and to start building it up which is what we need to do to protect our whole democratic system?" he asked.
Minister for Communications Richard Bruton said the Government provided €10m in additional funding to RTÉ last year, as well as additional money to TG4.
"We believe strongly in the need for public service broadcasting and the importance of broadcasting - be it provided by public bodies or indeed private sectors - and there are many excellent examples of public service delivery in the private sector as well," he said.
Minister Bruton said the Government is acting on the recommendations of the Oireachtas committee.
He said: "We will be having a tender to reduce the evasion rate on the license fee and we will be moving in due course to a model that is independent of the particular device a person has.
"I know RTÉ are acting on the more structural changes that are happening and the Deputy cannot be blind to the fact that there are huge structural changes."