AIB chief executive Mr Tom Mulcahy has insisted that the bank is precluded from answering media questions about its decisions to write-off debts owed to the bank by former politicians. The bank cannot comment on the loan to Mr Charles Haughey because the issues are under consideration at the Moriarty Tribunal and no comment was forthcoming on the loan to Dr Garret FitzGerald because of the onus on the bank of client confidentiality, he said.

On Mr Haughey's debt, he said: "The matter is in the public domain and we respect that. Equally there might be many things we might like to say on the matter but there are a number of reasons why we are not able to do so, the most important of which is that the Moriarty Tribunal has indicated to us that it would not wish us to comment on matters before the tribunal."

AIB has had "specific instructions" to this effect from the Moriarty Tribunal, he said. These instructions came in verbal form in the last week or so, Mr Mulcahy disclosed.

On the loan to Dr FitzGerald, he said: "There are a number of reasons why it would be difficult to respond . . . one of which would be client confidentiality. In a tribunal situation, if something comes along that we have to respond to, of course we will."

Asked if Mr Peter Sutherland as chairman of AIB and a director of GPA could have been involved in the writing off of Dr FitzGerald's loan, he said: "These matters are not dealt with by the chairman of the company. The chairmen of the company from time to time are non-executive directors . . . Decisions on credit matters would be taken at operational level . . . at management level . . . I would be very surprised if there was any involvement."

Asked if he could understand the concern of ordinary people that there was one banking policy for the rich and powerful and another for ordinary people, he replied: "I can understand the concern quite genuinely . . . I suppose what I would have to say is that there may be many things we could say if we were free to say them. But of course we are not from our perspective. But we have a rule about client confidentiality. We have it on good days and we have it on bad days . . . so we are very limited . . . If we see things in the public arena which we know are incorrect we cannot respond to them and this is if you like one of the frustrations of our position . . ."

He said he was not aware of any write-offs of loans to other former Taoisigh or politicians, insisting that all decisions would be made on a commercial basis.