The Minster for Public Expenditure and Reform has indicated that there may be conflict with trade unions over plans to cut allowances for public servants.
The minister is currently conducting a review of hundreds of allowances across the public sector which cost a total of €1.5bn a year.
At present, many of those allowances are deemed to be pensionable, thus inflating the cost of the state pension bill.
However, public service unions are likely to argue that allowances in the nature of pay cannot be cut under the Croke Park Agreement.
Brendan Howlin was speaking at the Oireachtas Committee on Public Expenditure and Reform, which was debating his legislation for a new pension scheme aimed at reducing the cost of government pensions.
Mr Howlin told the committee that the term "allowance" was frequently a misnomer, as the allowance was really core pay.
He cited the examples of his own ministerial allowance, and the allowance for being a school principal.
He said that in future it might be better to treat those allowances as core pay.
He told the committee that so far, Government departments have submitted a business case to retain around 800 allowances - though he noted that some of those business cases were "rather inadequate".
Mr Howlin was asked what would happen where a serving public servant was receiving an allowance, which he then decided would not count for pension purposes.
He said that in that case, the employee would retain the entitlement accrued to date, but would cease accumulating further benefit.
This definition of whether this counts as a pay cut is potentially extremely contentious - as pay cuts are not permitted under the Croke Park Agreement.
However, Mr Howlin told the committee that he has not yet discussed it with public service unions.
He said he would be bringing his review of allowances to cabinet shortly with his recommendation.
Fianna Fáil spokesperson Sean Fleming asked for a copy of the full list of allowances, saying he believed it must have been given to trade unions.
However, Mr Howlin said he had not given the list to anybody.
He said once the Government has made its decision, the document will be made public.
He noted that unions would not necessarily be in agreement with the Government position.
Asked how allowances could be reformed without the agreement of unions under the Croke Park Agreement, he said that would be a matter for debate.