AIB has agreed 100 deals with mortgage holders that have involved some form of debt write-off, according to the organisation which has been negotiating the arrangements.
The Irish Mortgage Holders Organisation also said one of the agreements has seen a Cork family get a €195,000 write-off of their debt. The family had borrowed €478,000 and will remain in their home.
The family will now have to service a mortgage of €200,000 and the balance of their borrowings will be warehoused or put to one side.
The bank has declined to comment.
The Irish Mortgage Holders Organisation said it is now dealing with 2,000 clients of AIB or its building society EBS.
It is also handling 360 clients of KBC bank.
AIB recently announced a controversial split mortgage product, which involved an automatic write down of some mortgage debt.
In a statement, Fianna Fáil finance spokesperson Michael McGrath called for greater consistency from the banks in dealing with mortgage arrears.
He said: "At present, there is a distinct lack of consistency across the different banks between the deals being achieved by borrowers in mortgage arrears.
"For example, the decision of AIB to grant some form of mortgage write off to at least 100 borrowers contrasts sharply with the policy of the other pillar bank, Bank of Ireland, which does not support debt forgiveness of any kind.
"One bank's sustainable solution could be another bank's unsustainable mortgage leading to repossession proceedings.
"For borrowers in difficulty with their mortgage, whether or not they are allowed to keep their home really shouldn't come down to a game of poker in this way."
Later, speaking on RTÉ’s Six One, Mr McGrath said there is a need for a transparent methodology which is published to ensure everyone is treated consistently in regard to mortgage debt forgiveness.
He said there is a difference of approach being taken by different banks in the State and that is not good enough.
He said the methodology must come from the Central Bank so that we know how borrowers might avail of debt write-down.
Mr McGrath said we need to know why a different approach is being taken by AIB and Bank of Ireland and people must be informed under what circumstances debt forgiveness will apply.
Meanwhile, AIB Mortgage Bank, a subsidiary of AIB, has agreed a €500m seven-year bond issue under its €20 billion mortgage covered securities programme.
In a statement, the bank said the seven-year deal was well-placed across 140 international investors from 20 countries and was also almost five times oversubscribed.
The deal was priced at a spread over mid-swaps of 95 basis points at a yield of 2.33%.
AIB said the bond issue is its longest since 2007 and further extends the maturity of its funding profile.
"The level of demand for the transaction is a vote of confidence from international investors in the progress that AIB has made and further demonstrates AIB's ability to consistently access markets at competitive pricing levels on an ongoing basis," the bank statement added.