The Labour Party leader, Mr Pat Rabbitte TD, has said the proposed referendum on citizenship is "flawed and dangerous".
Speaking ahead of Labour's party conference, Mr Rabbitte said the Government was "insisting on proceeding with a potentially divisive and damaging referendum ... in the hope of making electoral gain from it".
Calling for consensus and an "inclusive, decent, and humane" immigration policy, Mr Rabbitte said Fine Gael, Labour and the Green Party had agreed to table a joint amendment to the Referendum Bill when it begins its second stage debate next week.
If carried, the joint opposition amendment will result in the Bill being referred to an All Party Oireachtas Committee which will mandated to report within a matter of months.
Mr Rabbitte made his comments at a special eve of conference joint meeting of Labour's Parliamentary Party and the National Executive Committee in the RDS.