Finance Minister Sammy Wilson said they executive had to show efficiency
The Northern Ireland Executive will have to show "every effort" to make efficiencies before water charges can be introduced, Sammy Wilson has said.
The Finance Minister was speaking at a meeting of the assembly's finance committee on Thursday.
He outlined the pressures caused by rising costs in the water and sewerage systems, and fines for pollution arising from EU regulations.
He said average household water bills would be about £400 per year.
"That will be much easier to sell to the public if they feel we are not squandering money," he said.
A decision on the introduction of additional household payments for water and sewerage services has yet to be taken by the executive.
Mr Wilson told the committee that planning for next year's budget cuts was delayed three months because of the power-sharing dispute.
"We are trying to address it, and a committee has been set up to try to address how we get papers through the executive more quickly so that the kind of work that needs to be done by the committees is done and we don't finish up with accelerated passage (of legislation)," he said.
He accused ministers of creating further hold-ups by not taking the need for savings seriously.
"I am a bit disappointed that departments have not produced the spending plans," he said.
"Some of the suggestions that they made immediately had me saying 'come on, this is going to be a serious exercise, not a cynical exercise'. There's not really an excuse for the information not being provided to the committees."
Mr Wilson has established a £26m fund to allow departments to invest to produce long-term savings.
There is also a review of all sections of the budget to identify further efficiencies as there is expected to be no extra cash from London next year.