A cabinet minister believes people who paid their water bills cannot end up worse off than those who did not.
Controversy's continuing over the future of the system after an expert report last week recommended most families should not have to pay.
Leo Varadkar is among those who have rejected the idea that people who paid past bills should get their money back.
However he thinks they should not be put at a disadvantage: "Those who paid can't end up any worse off than those who didn't.
"The oireachtas committee which is dealing with this issue is going to have to work out exactly what that means.
"But, very briefly, there are two things that did occur to me, you know we do need to bear in mind that even now, there are still people paying for water.
"So you know we need to bear that in mind that they are not asked to pay for refunds, for general taxation and for refunds."