Names in a dossier of former politicians who allegedly held offshore accounts have been read into the Dáil record by Sinn Féin deputy leader Mary Lou McDonald.

Ms McDonald said it was not a case of her making allegations, “and I emphasise these are allegations”, but they had come from a very credible source.

The whistleblower, she said, alleged former ministers Des O'Malley (FF and later PDs) Ray MacSharry, Gerard Collins, Maire Geoghegan-Quinn, FF, "an S Barrett'', Richie Ryan, FG, and others, held offshore accounts.

Mr MacSharry and Ms Geoghegan-Quinn served terms as EU commissioner.

Ceann Comhairle Sean Barrett intervened to ask Ms McDonald if she was making allegations in the chamber.

She replied: “I am echoing the allegations that are very serious, that have been brought forward by the whistleblower.’’

Mr Barrett said Ms McDonald should know quite clearly, and if she had taken advice from the Clerk of the Dáil, she could not name names of people who were defenceless to contradict her.

Mr Barrett urged Ms McDonald to brief herself on what she could and could not do in a democratic chamber.

“And I wish to state quite categorically, in case anybody is under any doubts when you say ‘S Barrett’, it does not apply to me,’’ the Ceann Comhairle added.

Ms McDonald, who was speaking during Opposition Leaders’ Questions, said the whistleblower alleged matters of serious concern associated with very senior public figures, some of whom were still in receipt of State payments by way of pensions.

“The whistleblower has told us very clearly that he has gone to every length to have these matters explored and investigated,’’ she added.

“And the whistleblower now fears that will never happen.’’

She said the allegations of a serious nature had been made against named persons, and there were the more serious allegation that there was a connivance to avoid or even cover up the exposure of those matters. Given that the Public Accounts Committee (PAC) was not permitted to investigate those matters what did Taoiseach Enda Kenny proposed to do ?

She also asked if Minister for Enterprise Richard Burton would allow the whistleblower to complete the investigation or would the Taoiseach propose another mechanism for the full examination of those issues.

Mr Kenny said a law had been introduced for whistleblowers to bring forward certain matters of information they felt relevant and important in the public interest. The law was framed to protect the whistleblower.

He added the Garda fraud squad investigation unit made a formal request for a witness statement to be forwarded by Mr Bruton. The Minister had explained why that was delayed and had confirmed that it had been forwarded to that arm of the State with particular specific responsibilities and powers.

He would expect the unit to follow through and act upon the witness statement, he added.

A statement from Máire Geoghegan Quinn said: “I have never had an Ansbacher Account. Neither have I ever had an account with Guinness and Mahon Bank.”