Capital spending in areas such as housing may have to be cut in order to cover the cost of refunding water charges.

The Minister for Finance told TDs this morning that the total cost of covering the refunds will be €178m – including a €5m bill to cover administrative costs.

He told the Oireachtas Committee on Budgetary Oversight that the repayments will be dealt with later in the year – following the Taoiseach Leo Varadkar’s commitment to deliver a full refund to everyone who paid their charges.

Fianna Fáil spokesperson on public expenditure and reform Dara Calleary said the Taoiseach had made the commitment in a Sunday newspaper – without making it clear where the money would come from.

Sinn Féin spokesperson on finance Pearse Doherty meanwhile, said it made no sense to divert funds from housing while the homelessness crisis is ongoing.

Minister Donohoe said the under-spend is a direct result of the decision to scrap water charges and refund bills – something he said his party had argued against.

“We can’t have our cake and eat it here,” he said.

“We can’t be in a situation where the Oireachtas decides and political parties decide they want to pay for this out of Government expenditure and they want to pay for this out of taxation and then, when I look to try and do it, then be in a position where people say, ‘hang on the choices you are making are wrong.’”

Fianna Fáil has complained that there has been no conversation over when or how the refunds should be paid out - and has written to the government expressing concern over the lack of clarity as to where the funds are coming from.