Taoiseach Enda Kenny has said the Budget will be carried through despite hundreds of people protesting outside the Dail.
Tanaiste Eamon Gilmore also poured cold water on calls for the Government to row back on its cut to the respite care allowance, which will see thousands of people caring for sick loved ones lose 325 euro a year.
As hundreds of angry carers picketed Leinster House calling for a U-turn, Mr Kenny said the 3.5 billion euro of spending cuts and tax hikes announced on Wednesday were difficult but necessary.
"This will be the most difficult Budget in the lifetime of this administration," Mr Kenny said. "The decisions have been discussed, debated and made by Government and will be now carried through."
Public Expenditure Minister Brendan Howlin earlier said the controversial cut was regrettable, but savings had to be made somewhere. He said slashing the respite care grant from 1,700 euro to 1,375 euro a year enabled the Government to protect core payments of social welfare and the core weekly carer's allowance.
But the Disability Federation of Ireland (DFI) said Budget 2013 had hit disabled people and their families hard. Chief executive John Dolan said the respite care grant cut, a tripling in prescription charges for medical card holders and reductions in the household benefit package, left them more vulnerable.
The cuts and tax hikes unveiled were part of the sixth austerity budget Ireland has been forced to endure since the onset of the economic collapse.
A number of Labour backbenchers were reportedly seeking meetings with senior ministers to express concerns over the cuts, which will also see parents lose 10 euro in child benefit for each of their first three children.
Labour councillor Cian O'Callaghan described the budget as Fine Gael-led and appealed for TDs in his party to vote against the Social Welfare Bill in which many of the cuts will be implemented next week.
Siptu general president Jack O'Connor wrote to the Taoiseach calling for him to intervene to bring forward the Budget measures curtailing pension tax relief for top earners from January 2014 to July 2013. He said it would generate 125 million euro of tax revenue in 2013, which could be used to offset cuts.