It is the first day back for the Dáil after the summer break and tax will be high on the agenda.
Finance Minister Paschal Donohoe wants to widen tax bands in the budget and he has got the backing of business group, IBEC.
Fine Gael wants to widen the bands to stop people hitting a high rate of tax too early.
Fianna Fáil says cutting the Universal Social Charge (USC) has been agreed and is set down in the Confidence and Supply Agreement between the parties.
On Tuesday, IBEC's chief economist Fergal O'Brien told the Budgetary Oversight Committee that altering the tax bands is the way to go.
Minister Donohoe and Fianna Fáil are due to meet later this week.
Micheál Martin and Leo Varadkar will face each other when the Dáil resumes at 2.00pm.