Taoiseach Micheál Martin has urged the Oireachtas to bring closure to its dispute with former Rehab Group CEO Angela Kerins.
He also believes there should be a comprehensive response from the Oireachtas and he has raised this with Ceann Comhairle Verona Murphy.
As first reported in the Irish Independent, it is understood that Mr Martin has written to Ms Kerins in response to correspondence received from her.
In 2014, Ms Kerins was questioned for seven hours by the Public Accounts Committee (PAC) which was examining Rehab's finances.
The Supreme Court found that the PAC had acted unlawfully by subjecting Ms Kerins to questioning that went beyond the scope of its terms of reference.
The then chief justice Frank Clarke stated that the committee had conducted a public hearing that significantly exceeded the invitation originally issued to Ms Kerins and that its approach was inappropriate for a parliamentary committee.
The court could not grant her compensation or an apology - only the Oireachtas could provide a remedy.
She continues to seek this remedy.
The then ceann comhairle, Seán Ó Fearghaíl, apologised to Ms Kerins in 2019.
But within days he issued a clarification stating that he had done so in a personal capacity and was not speaking on behalf of the Dáil.
Earlier this month, Ms Kerins spoke to RTÉ's Prime Time programme.
She said she felt "trapped" at the PAC during what she saw as a one-sided interrogation.
"You have no ability whatsoever to defend yourself. There was no equality of exchange of information," she said.
"We went, came in to give them as much information as possible so they could see what was being provided for the fees [paid to Rehab by the State]," she said.
Ms Kerins also said she was still waiting for an appropriate remedy from the Oireachtas.
"The Oireachtas itself has to provide a remedy for me," she said, "I'm now having to go back to my abusers for justice," she said.
Ex-Rehab CEO says she's still 'seeking justice' for PAC grilling
The Houses of the Oireachtas did not issue a comment today in response to queries from RTÉ News.
However it is understood that the Oireachtas has previously offered to pay half of Ms Kerins' Supreme Court costs in the second module of her case.
In his letter to Ms Kerins, seen by RTÉ News, Mr Martin told the former Rehab CEO that what happened to her should not have happened.
"I regret greatly the harm that you experienced as a result of the Committee's conduct towards you.
"I know it had a significant adverse impact on you, including on your health and well-being, and I do hope that you have been in a position to experience some recovery from that in the intervening period."
He also said that the Houses of the Oireachtas were the responsible body for the organisation and the conduct of the business of the Houses and the members.
"As Taoiseach, I do not have a directive power in respect of those responsibilities of the Houses of the Oireachtas.
"However I am very conscious of the concern that you express about seeking a route to vindicate your position in circumstances where the Courts are not available to you."
In a statement to RTÉ News, Mr Martin's spokesperson said: "The Taoiseach received correspondence from Angela Kerins, which he has responded to in writing.
"The Taoiseach is very conscious of the Supreme Court decision and recommendation. He believes there needs to be closure to this matter.
"The Taoiseach believes there should be a comprehensive response from the Oireachtas. He has raised this with the Ceann Comhairle.
"The responsible body in respect of the conduct of the business and the Members of both Houses of the Oireachtas are those houses themselves.
"The Taoiseach will meet Ms Kerins."
