Taoiseach Micheál Martin has claimed the banks were not bailed out following the 2008 financial crisis.
In 2010, Irish banks were given upwards of 64 billion euro in State liquidity, borrowed from the European Union and the International Monetary Fund (IMF).
The figure, then equal to 40% of Ireland's economy, will continue to be paid for generations to come.
Mr Martin shocked the Opposition benches on Wednesday when he denied what took place was a bailout.
He told the Dáil: "The banks were not bailed out. Shareholders in the banks were not bailed out.
"The State took equity. The shareholders were not bailed out. That is not a popular thing to say, but it is a fact."
The Taoiseach was responding to a question from People Before Profit TD Richard Boyd Barrett, who was raising the issue of striking workers at Debenhams who have been made redundant.
He said a three million euro Government offer for retraining was an insult, noting that the Government had found 64 billion euro to bail out the banks.
He said: "The failure by the Government to ensure justice for these workers is appalling.
"I remind the Taoiseach that he said he could not put money on the table because it would set a precedent.
"The sum of 18 million is owed to the State by Debenhams. The Taoiseach did not mind setting a precedent when it came to bailing out banks to the tune of 64 billion.
"There was no moral hazard there or no worry about the implications, but when it comes to workers who have worked for decades, who have done nothing wrong, and who are entitled to the two plus two, agreed with Debenhams, we cannot underwrite them."
Mr Martin accused Deputy Boyd Barrett of engaging in "populism" with the remarks.
He said: "Deputy Boyd Barrett never wants to hear the facts because he lives in a fantasy economic wonderland. If his party ever got into power thousands of jobs would migrate from this country. That is the reality."
Mr Boyd Barrett shook his head in response to the Taoiseach's claim that banks were not bailed out and responded: "They were."
Dail records show that Mr Martin has repeatedly referred to the Irish bank bailout in parliament since 2010.
The Taoiseach was widely mocked on social media over the comments, most notably by Sinn Fein leader Mary Lou McDonald.
She tweeted: "The banks were NOT bailed out sez (sic) Taoiseach Micheal Martin."