The Tánaiste, Ms Harney, has denied any conflict of interest between her party's policies on air transport and donations from Ryanair.
She told the Dáil she had informed the Cabinet about a donation in 2001 before there was any discussion about the development of an independent terminal at Dublin Airport or the break-up of Aer Rianta into three autonomous airport authorities. "I make no apologies to anybody for the policies I pursue."
She insisted that nobody could suggest there was any conflict of interest.
"Nobody has carried out more inquiries under company law into vested interests in this country than I have."
The Minister for Enterprise, Trade and Employment also said she did not believe an independent terminal at Dublin Airport should be owned or operated by an airline.
"Clearly that would be a conflict of interest. The use and owner of that facility would have to be separate."
She was responding to the Labour leader, Mr Pat Rabbitte, who pointed to the claims by Aer Rianta chairman Mr Noel Hanlon that the legislation to break-up the airport authority company, the State Airports Bill, was being driven by the vested interests of a large commercial organisation.
He also referred to Ms Harney's comments in the Dáil on Wednesday about a €5,000 donation from Ryanair, and suggested she might want to "amend" the Dáil record given remarks by former Fianna Fáil minister Senator Mary O'Rourke about a €63,000 donation from Ryanair to the Progressive Democrats.
Ms O'Rourke had called on individuals and parties involved in framing aviation policy to "re-declare" any donations they received from Ryanair.
Ms Harney insisted that nobody could suggest there was any conflict of interest for her.
She said the disclosure limit for donations under new legislation was €5,000.
The "sum of money involved has been in the public domain for some time. I informed the Cabinet of that matter in 2001 before there was any discussion on this issue.
"It was put into the public domain at that time, and nobody was in any doubt about that donation. That was prior to the new limits on funding."
Insisting she had nothing to apologise for in her policies, she said they "are in the national interest, and in the interests of passengers, tourism, business and especially in the interests of Shannon and the regions" .
The debate arose in a dispute over the alleged rush to introduce the State Airports Bill.
