The climate action watchdog is opposing Government plans to delegate to it the task of setting carbon budgets.
It says the Government must be responsible for telling the public, industry and other sectors how much they must reduce their carbon emissions.
In a letter to Climate Action Minister Richard Bruton, the Climate Change Advisory Council says its job should be to advise on government proposed budgets.
It says it is happy to assess such budgets to see if they are feasible and sufficient to meet the country's national and international carbon reduction commitments. But making it legally responsible for setting budgets, as required by the draft Climate Action Bill, would not be appropriate.
The letter is signed by council chair Professor John FitzGerald and states: "The council strongly recommends that, contrary to the procedures outlined in the draft legislative proposals, it would be more appropriate that Government propose and set carbon budgets.
"These would then be reviewed by the proposed Climate Action Council for their ambition and feasibility against the national targets.
"The Climate Action Council should not be in a position where it might be perceived as setting national targets to be enshrined in legislation.
"Moreover, the Government is better placed to engage sectors and the general public to ensure 'buy-in' and acceptance of carbon budgets.
"Following on from this understanding, the council does not consider it appropriate that the proposed Climate Action Council, as an appointed body, should propose carbon budgets."
Carbon budgets are a key feature of the national climate action plan. The idea is to prepare five-year national budgets that clearly set out how much greenhouse gas the country as a whole can emit over the period in order to cut emissions in line with national and international commitments.
Once a budget is agreed, individual targets will be set for each sector, such as industry, transport, agriculture and energy.
Similar models are used in other countries and help to clarify exactly what each sector of society must do to cut carbon emissions. Ireland's previous carbon reduction plans have been heavily criticised for being vague on targets and lacking clear pathways to reach them.
The process is complex and certain to be contentious, however, and, with the first budget meant to cover the 2021-2025 period and still no Climate Action Bill enacted, it is already behind schedule.
Prof FitzGerald said while the UK and New Zealand used models similar to that proposed in the bill, he believed it risked "impairing the ability of the council to independently assess carbon budgets that it originally put forward".
Prof Fitzgerald told the Irish Independent if the Oireachtas adopted the model set out in the bill, the council would do as legally required of them.
"But I do feel there is a risk of confusing whose budgets these are. It is for the Oireachtas to agree what the country must do and we will certainly assist in that," he said.
"But you would not ask the Fiscal Advisory Council to set financial budgets for the country and then also assess those budgets. I think we should operate in the same way."
A spokesperson for the Department of Communications, Climate Action and Environment said: "The drafting of the Climate Action Bill is continuing and the submission made by the council will be considered during the drafting process."