A new report today claims to have revealed the full scale of debt write downs approved by IBRC.
The Sunday Business Post reports that a combined total of between €1bn and €1.2bn was written off for 40 customers (businesses and individuals).
The paper also claims the proposed Commission of Investigation into the bailed-out bank will examine its tax affairs.
The Government this week unveiled plans for the investigation, which will examine all write-offs at IBRC worth over €10m - as well as any special interest rates which resulted in borrowers saving more than €4m.
Finance Minister Michael Noonan says he wants the new report to be completed by the end of the year.
Fianna Fáil leader Micheál Martin welcomed the move to establish a "proper" commission earlier this week, but raised several concerns about the way the Government has dealt with the situation to date.
During the week Enda Kenny called Government plans for an IBRC probe 'right and proper'. The Taoiseach also said he does not regret not calling for a full inquiry when the SiteServ controversy arose in April.
He welcomed the High Court ruling earlier this week which allows media outlets to report Catherine Murphy's comments to the Dáil about businessman Denis O'Brien's relationship with IBRC.
