Bank of Ireland's group chief executive Richie Boucher has said the bank would try to veto any insolvency arrangement (PIA) which includes a mortgage write-off.
For a personal insolvency arrangement to be approved, a majority of the creditors must vote in its favour.
Mr Boucher's statement means the bank will vote against any PIA which involves writing off part of a mortgage debt owed to it.
The statement was described as "appalling" by Sinn Fein's Pearse Doherty at today's Oireachtas Finance committee meeting.
The Bank of Ireland boss admitted the bank does write off debt if a customer goes through insolvency or bankruptcy.
During sustained tough questioning from members of the Finance committee, Mr Boucher said "we are not doing it voluntarily."
Mr Boucher said it was "not a policy or a practice" of the bank to write off debt.
However, he added that "there is a write-off if the customer goes insolvent or bankrupt."
Bank of Ireland's position has been in contrast to rival AIB which has advocated debt write-off as a policy in certain circumstances.
The committee hearings on mortgage arrears and the resolution process being offered by banks to those in mortgage distress continues today.
Stephen Mason, from Bank of Ireland's mortgage division, told the committee that the bank had offered forbearance to nine in ten customers in arrears.
Mr Mason said 86% of customers were meeting their arrangements compared to 77% for the remainder of the industry. He said they had proposed solutions to 64% of customers against a Central Bank target of 50%.