The outgoing Irish representative on the European Court of Auditors wrote an email criticising Kevin Cardiff, his proposed replacement, it has emerged.
Eoin O’Shea sent the correspondence to two members of the Budgetary Control Committee that voted down the nomination of Mr Cardiff yesterday.
In the email he highlighted how Mr Cardiff had been in a senior position at the time of the banking collapse in Ireland.
He also highlighted the €7bn transactions between Anglo and Irish Life and Permanent to hide transactions in Anglo accounts.
Mr O’Shea said he sent the email in a “moment of madness” after finding out he would not be nominated to stay in his job.
Mr O'Shea was giving evidence before the Joint Oireachtas Committee on European Affairs this morning.
He said he has since apologised to Mr Cardiff.
"At that stage I may have been a little angry in relation to the matter," he said today.
"I have subsequently revised my opinion, having met the gentleman… and understood his interest in the position.
"I would apologise to him for sending that email - I did it in a moment of heat."
The text of the email was subsequently read out by Deputy Joe Costello in the committee.
"I just wanted to let you know the Irish Government had decided to replace me at the Court," read the email.
"Their suggestion is an Irish civil servant who was responsible for financial supervision during the period of the collapse of the Irish banks," it continued.
"I believe there will be further details in respect of this appointment, which will be of interest to the Parliament because of the Irish prosecutorial interest in whether or not the State condoned in the window-dressing of the financial accounts of Irish financial institutions in respect of €7bn."
Meanwhile, the Taoiseach said Mr Kevin Cardiff will remain Ireland's nominee to the European Court of Auditors despite being rejected by MEPs yesterday.
His nomination will now go before a vote of the full European Parliament next month, but opposition parties have called for his name to be withdrawn.
"Mr Cardiff performed very competently at the committee and the view expressed is that the result doesn't reflect the quality of the hearing," Mr Kenny said.
"Obviously the process is not completed yet, and this is a decision for the entire European Parliament and not for a small group, committee or otherwise, within the Parliament."