The Junior Minister responsible for water charges says households will still receive some water free of charges.

But Fergus O'Dowd says no decision has been made on exactly how much water each home will get before charges kick in.

Senior staff from Irish Water are due to face questions from TDs at the Public Accounts Committee (PAC) this evening about the total spend by the agency.

Last night the water provider said it wanted a system where people would be charged a minimum amount, even if they did not use any water.

But Minister O'Dowd says the government is committed to giving some free water.

Earlier the Environment Minister said it was not "his business" to know the extent of spending on consultants by Irish Water.

Phil Hogan says he does not micromanage semi-state bodies and has defended the €86 million paid to external firms.

The said the handling of the Irish Water controversy is not a public relations disaster for the government - saying "you can't make an omelette without breaking eggs".

He says the total spent was appropriate and it was not for him to micromanage.

Sinn Fein has meanwhile called on Minister Hogan to resign over his handling of Irish Water.

Party leader Gerry Adams says it is not acceptable for a Minister to admit he has not been watching where public money is spent.