AIB has refused to rule out mounting High Court legal challenges against any successful appeal by customers over tracker mortgage redress entitlements.
There are 117 appeals regarding AIB tracker cases before the Financial Services Ombudsman; comprising people unhappy with the terms of their compensation offers and others who feel unfairly excluded from the redress scheme.
Asked by Sinn Féin finance spokesperson Pearse Doherty, at the Joint Oireachtas Finance Committee, if he could guarantee the bank would not challenge any successful appeal by customers, AIB boss Bernard Byrne said "I can't give that guarantee as I don't know the circumstances of each case."
AIB has been dealing with nearly 10,000 cases and has put aside €230m to cover compensation.
The overall tracker scandal - which saw borrowers of all the main lenders wrongly removed from tracker loans and put on more expensive mortgages - is expected to grow to 40,000 cases and €1bn in costs when finally dealt with.
AIB also said that the 500 additional tracker cases that have come to light at its EBS subsidiary will be fully back on proper rates by the end of June and compensated by the end of September.
Mr Byrne said AIB only recognised these cases as being worthy of the tracker investigation after being pressured by the Central Bank on the matter.
Mr Byrne told the Finance Committee that AIB has not - unlike some other banks - set aside any provisions to cover potential fines and penalties that could be handed out by the Central Bank for its role in the tracker scandal.
He said AIB remains "ready and open" to address any other cases should they emerge.