The Taoiseach, Mr Ahern, has said that any tax liabilities owing to the State must be discharged, whether those who owe the money are private individuals or financial institutions.
Speaking in Cork, where he canvassed on behalf of Ms Sinead Behan, Fianna Fail's candidate in the forthcoming Cork South Central by-election, Mr Ahern left the position in no doubt.
In the early 1990s, as minister for finance, he had given the Revenue Commissioners newer and tougher powers.
The Commissioners were already actively engaged in the investigation of "more than one financial institution," and would use those powers to get to the root of claims that AIB's liabilities to the Exchequer were outstanding to the tune of £86 million, as reported by Magill yesterday.
Suggestions that there had been a deal between the Commissioners and AIB were a matter of speculation, Mr Ahern said, but did not preclude the bank being pursued for lawfully-owed debts. The Revenue Commissioners had stringent powers on their side and would use them.
The Minister for Finance had also made it clear that if those powers needed to be strengthened, the Government would make it happen.
He added that any irregularities concerning past or present dealings would be investigated by the Commissioners - "and the sooner the better."
"The law says that if there are liabilities to do with non-residential accounts, they have to be investigated. There is no closed deal regarding these matters and neither should there be.
"Thankfully, because of the tough powers I gave the Commissioners as Minister for Finance, they can look at the controls and procedures as they are now or as they were in the past.
"Whoever has tax liabilities must pay them - that's the way it's got to be and I believe the Commissioners will follow whatever institution or individual to the Nth degree.
"If bogus non-residential accounts were used to avoid non-payment of tax, the matter will be pursued - it's the job and function of the Revenue Commissioners to recover outstanding monies.
"The integrity of the service must to be upheld and all outstanding liabilities must be paid.
"Whenever people are shown to have been involved in defrauding the State, whether individuals or financial institutions, whenever that happens it must be dealt with," Mr Ahern said.