AIB has said it is unable to quantify any potential tax liabilities it may incur as a result of the Dail Committee of Public Account's (PAC) inquiry into bogus non-resident accounts.

The bank has made a contingent liability provision in its accounts for any arrears and penalties which may be demanded by the Revenue Commissioners in line with accountancy standards.

In a note to the accounts, AIB said the directors cannot reliably estimate the amount or range of any obligation in respect of DIRT as they have no reliable basis for so doing.

The Office of the Revenue Commissioners is currently carrying out audits at the State's financial institutions and has been charged by the PAC with raising demands for any tax arrears together with interest and penalties on those amounts. AIB maintains that it had secured an amnesty with the Revenue, which involved the write-off of DIRT liabilities between 1986 and 1990. The PAC found there was no evidence of such a deal.

Estimates of the potential DIRT bill at AIB have ranged from £35 million to £100 million (€44-€127 million). Much will depend on the extent of the audits and the view the Revenue adopts on whether tax is due on non-resident accounts with incomplete documentation.

Mr Mulcahy said the PAC judgment was an opinion. "The charging agency is the Revenue, not the PAC. The audit is continuing." AIB refused to disclose the cost to the bank of defending itself at the inquiry.