The Irish Council for Civil Liberties (ICCL) has said it was "appalled" to learn of the extent of the amendments to the Freedom of Information Act proposed by the Government and published this morning.
ICCL director Ms Aisling Reidy said the proposed amendments were designed to inhibit and prevent access to information.
"The manner in which the Government has approached its efforts to curb the right of citizens to information on how the government they elected is run is quite extraordinary, " Ms Reidy said.
"The impetus for these changes has come through a secret report conducted by civil servants without the input even of the information commissioner, not to mention the NUJ [National Union of Journalists] or any citizens who are the actual beneficiaries of the Act.
"To cloak in secrecy a revision of the Freedom of Information Act is not only contradictory, but makes a mockery of the values of transparency and openness which the Act was intended to engender," Ms Reidy said.
NUJ Irish Secretary Mr Seamus Dooley said the act confirmed the union's worst fears that the Government is attempting to "castrate" the Freedom of Information Act by removing some of its most useful provisions.
He said curbs on the release of letters between Ministers and the introduction of a charge were of particular concern, as was the extension of the exemption of Cabinet records from five to ten years.
Mr Dooley challenged the Tánaiste, Ms Harney, "to come out from behind her civil servants" and publicly debate with the NUJ the reasons for her abandonment of the principles of more open government.
The Labour Party has accused the Government of attempting to hide "embarrassing" information from the public. Ms Joan Burton, Labour Party spokeswoman for Finance, said the Bill will copperfasten "the culture of secrecy" in Irish public life.
Other provisions of the Bill include up-front fees for people requesting information under the Act to cover administrative costs, and charges relating to the work of tribunals, public inquiries, parliamentary documents and papers.
Ms Burton said the Bill will effectively make the exemption for Cabinet papers mandatory, not discretionary; will extend the exemption to inter-Ministerial correspondence; and will broaden the definition of papers under the Act to include many documents that are currently outside the parameters of the Act.
"In a welter of technical amendments to the original Act, there is a core central message - material capable of causing political embarrassment is to be sheltered from the critical gaze of the public," Ms Burton said.