Labour TD Willie Penrose has said there is no point in delaying the inevitable on water charges and consumers who have already paid should be refunded.
The Labour Party earlier published a bill to refund customers who have paid their water charges.
The party says that given the proposed suspension of charges, those who have paid must be treated the same as those who did not.
The bill provides for full refunds within six months.
Party chairman Willie Penrose said a situation could not arise where those who had complied with the law were left feeling as if they had been mugged.
Former minister for the environment Alan Kelly said what he called the "Fianna Fáil-Fine Gael axis" had committed environmental treason by abolishing water charges.
He said customers were being made fools of and he said the 950,000 who paid must be repaid along with those on group water schemes.
Mr Penrose said the Department of Social Protection should also seek to get back the €100 water conservation grant.
Speaking on RTÉ’s Six One, he said the bill aims to ensure there is a level playing pitch, protecting consumers who have obeyed the law.
Deputy Penrose said that the Labour Party does not want to see state-sponsored discrimination.
"We don't want people being made a fool of, or being mugged. People who obeyed the law must be treated equally. Let's do it quickly and stop fooling around."
He said the arrangement between Fine Gael and Fianna Fáil does not specify what is going to happen about charges already paid.
Mr Penrose said that "as sure as night follows day the charges are effectively dead in the water".
As for Junior Minister Finian McGrath not having paid his water charges, Mr Penrose said Mr McGrath should pay because “he is obliged to”.
A spokesperson for Mr McGrath has said he is seeking the advice of the Attorney General on whether he must pay the water charges and will also consult with his Independent Alliance colleagues.
Mr Penrose said he was shocked that any citizen of Ireland would seek the advice of the Attorney General as to whether they should pay their bills.
Meanwhile, Fine Gael has dismissed Labour's proposal to repay water charges as a headline grabbing stunt.
Dublin North-West TD Noel Rock said their position was that after the final decision is made on water charges, either everyone will be paid back or those who did not pay before the suspension would be pursued for the money.
He said this was the position on equal treatment as per the agreement between Fianna Fáil and Fine Gael on minority government.