FIANNA Fail leader Micheal Martin yesterday moved to exclude the bank guarantee from his apology for his party's mistakes in power.
On Saturday, Mr Martin had used the early stages of his first keynote address to a party national conference to make his apology.
He promised "no half-apology" but yesterday said that the "jury is still out" on whether the Fianna Fail-led government should have guaranteed the debt of Irish banks in 2008.
Mr Martin said yesterday he was apologising for the economic policies of too much spending, and reducing the areas where tax can be raised.
And he said that the form of the guarantee was not in question, rather the scale of it.
"I think the jury is out on the banking guarantee," Mr Martin said.
However, leading economist Colm McCarthy told party grassroots members at the Fianna Fail Ard Fheis that the guarantee was "a mistake".
The UCD economist was speaking as an expert panellist at the Ard Fheis. Regarding the current bank debt repayments, Mr McCarthy said it was unprecedented for a country in an IMF programme to be paying back unguaranteed bondholders.
Mr Martin's address to the party faithful was notable in that it happened on a day when former Taoisigh Bertie Ahern and Brian Cowen were also in attendance.
Mr Martin admitted the party should have acted differently in its handling of the economy, with policies that contributed to the fall of the Celtic Tiger and Ireland's epic property crash.
And he said it wasn't enough to point to "the worst world recession in 80 years and the eurozone crisis".
He also said Fianna Fail couldn't point to other parties demanding policies that would have made the situation worse.
"We were in government and we should have acted differently. We made mistakes. We got things wrong.
"And we are sorry for that," he said to a standing ovation from nearly 3,000 party activists.
"No equivocation. No half-apology. Just the plain unvarnished truth," he said.
Mr Martin added: "People were angry and they showed it, delivering a historic defeat for us.
"We fully acknowledge the scale of the defeat.
"That is why we must now work for a deep and real renewal of both our party and of politics as a whole."
Mr Martin also set out his party's position on its role in opposition.
"If you want destructive opposition, if you want a replay of the deeply cynical opposition politics seen before the election, then go elsewhere," he said.
"If you believe in renewing the progressive republican tradition which built up this country, then join us."
Mr Martin received support from the unlikeliest of quarters as Fine Gael welcomed his apology "and the acknowledgment of Fianna Fail's role in Ireland's present economic problems".
"It is to be hoped that he will keep his promise to provide constructive opposition, and to help get this country out of the crisis caused by a government of which he was a minister," a party statement said.