Those responsible for the tracker mortgage controversy must be held to account, the Fianna Fail Ardfheis has heard.
Party finance spokesman Michael McGrath asked how all the banks could have made the same mistake.
He warned financial institutions to repay immediately the remaining mortgage holders who had not been refunded and to compensate all customers immediately.
The Cork South-Central TD told delegates: “I am sure many of you are curious like me as to how all the main banks made the same mistake. We need answers.”
And he said the Central Bank would be "rigorously questioned" when its representatives come before the Oireachtas Finance Committee next week.
The final figure for the number of people wrongly removed from their tracker mortgage has been estimated in some quarters at up to 30,000.
Some 7,000 cases had already been dealt with before the Central Bank examination started in 2015 and it has confirmed that by the end of June 12,500 affected customers had been identified.
Earlier this week Fianna Fáil Oireachtas finance committee chairman John McGuinness called for the banking licence of offending banks to be restricted.
Mr McGrath told the ardfheis the handling of the controversy had been a disgrace.
“Customers were overcharged - often by hundreds of euro every month, for many years. To put it in plain and simple language: the banks took their money.”
‘Lives turned upside down’
He said “some customers lost their home as a result. Others had their lives turned upside down, their dreams shattered.”
Mr McGrath said he wanted to send out a clear message from the ardfheis.
“It is not good enough. Those who have not yet been repaid need to be repaid now.
“Customers should be compensated immediately and people have to be held accountable for how this happened in the first place.”
Public expenditure spokesman Dara Calleary said Fine Gael had failed to build social housing because it was "not in their DNA".
In a sharp attack on the Government’s housing policy, he said they had been told the problem was not the lack of money.
“So one must ask, why have so few social houses been built? The simple answer is that Fine Gael do not want to build social housing, it is not in their DNA.”
He added: “It’s also not in their DNA to encourage affordable houses, to allow people to achieve the dream of owning their own home.
“We will continue to pursue them and put forward deliverable policies in this area.”
The Mayo TD said “the dog in the street can tell you the State simply needs to build more social houses”.
He said there had been countless press releases action plans, announcements, updates and reviews from the Government “yet no action”.
Just 4,000 new social houses had been built since 2011, fewer than Fianna Fáil built in almost every year from 1994 to 2009, he said.