The chief executive of Ryanair, Michael O'Leary, has told the Oireachtas Committee on Transport that the conditions were right now for his airline to buy Aer Lingus.
Mr O'Leary said that under the deal he was proposing, the Government would get control of the Heathrow slots, Ryanair would recognise the unions and respect procedures already in place.
He also said the current management would remain in place and passenger numbers would increase to 18 million in five years.
Mr O'Leary argued that a merger would strengthen competition.
During questioning, Labour TD Tommy Broughan told Mr O'Leary that his promise to recognise the unions was like Osama Bin Laden coming out and saying he is becoming a Christian. The Ryanair chief executive told the committee Ryanair had to recognise all the stakeholders in Aer Lingus, including the unions.
Also at the hearing, Aer Lingus has been told that unless it re-instates a Shannon to Heathrow service, there would be considerable support among TDs for the Ryanair takeover bid. A number of TDs from the Shannon region said there was still a lot of anger there, about the pull-out.
Aer Lingus's CEO Dermot Mannion said the airline would be issuing its defence document, on the Ryanair bid in a few days - and that was as much as he could say for now.
The airline's Chairman Colm Barrington said he had not heard of an Irish investor mentioned in a media report today as considering a counterbid to Ryanair's €750m offer.
Meanwhile, business group Chambers Ireland has said Ryanair's new bid for Aer Lingus should not be approved because of competition concerns.
The group's Air Transport Users Council said that while both airlines had solid records of reducing ticket prices, this would be threatened by a merged airline.
Spokesperson Seán Murphy said that if a merger were approved, it would give rise to the new airline's becoming a de facto monopoly buyer of services at the Republic's main airports.
Mr Murphy said that if a merger were successful, there would have to be safeguards, such as ensuring that the Dublin to London Heathrow slots were secured 'in perpetuity' for Ireland, while allowing a rival such as EasyJet to compete on the route.
The ATUC statement comes ahead of a Joint Oireachtas Committee on Transport hearing at which Ryanair chief Michael O'Leary and his Aer Lingus counterpart Dermot Mannion are to appear.
