Socialist Party TD Joe Higgins is defending the use of a Dáil travel allowance to fund his role in the anti-household charge campaign.
Deputy Higgins said it is entirely justifiable for TDs to use their expenses to travel the country campaigning against the tax.
"I believe that the allowance that is facilitated to me as a TD to try and represent the people who are opposed to having the burden of austerity, of bondholders and developers put on their shoulders - I believe that they would be very comfortable with the modest use of expenses," he said.
"I never stayed in five-star hotels or traveled in luxury," he added.
He has also described the issuing of warning letters to householders who have not paid as a "bullying tactic".
People will be sent three warnings before receiving a court summons.
Deputy Higgins says people who are opposed to the charge would support Dáil allowances being used in the campaign.
"The majority who are boycotting would be very happy that any such expenses would be used to support them in opposition to another odious attack," he said.