Business group IBEC says the proposed sale of Aer Lingus to International Airlines Group (IAG) would be beneficial for the company, for tourism and for inward investment.
The body has appeared at the Oireachtas Transport Committee, alongside tourist groups, the IDA and Enterprise Ireland.
Concerns have been raised about connectivity issues for regional airports in particular, if the takeover went ahead.
IBEC polled its thousands of its members on their thoughts on the sale - and said consensus was hard to reach, but was a rare positive voice before the committee.
Mary-Rose Burke set out out the position of IBEC on the proposed sale.
Both the IDA - whose clients include Google and Facebook - and Enterprise Ireland, which represent Irish exporters, said connectivity was vital to their thousands of client companies.
They also said more information would be needed on future plans by IAG for Aer Lingus before they could back a sale.
Niall O'Donnellan of Enterprise Ireland said his clients want clarity on a number of issues.
Cross-party politicians raised their constituents' fears about the regional airports being left behind. Dessie Ellis of Sinn Fein called for a referendum on the issue.
And Stephen McNally of the Irish Hotels Federation made the following plea.
IAG has pledged to use Heathrow slots for Irish routes for a minimum of five years if the deal gets the go ahead.
The group pledged yesterday not to sell the slots without government approval.
IAG issued a statement after Taoiseach Enda Kenny said he would not consider any sale unless he had a guarantee about the future of the Irish routes to Heathrow. The group is offering "legally-binding commitments".
These include: a guarantee that the Heathrow slots cannot be sold - even to fellow IAG airlines - without the government's approval; the Aer Lingus company name, head office location and place of incorporation will all remain in the Republic of Ireland, and will need government agreement to move - and to continue operating a service to Ireland from those Heathrow slots for the next five years.
IAG is looking to buy the government stake in Aer Lingus, in a deal worth €1.4bn.
Pat Byrne is the chief executive of Rainmaker Business Technologies, and non-executive chairman of Cityjet.
He told Newstalk Brekfast earlier that the offer is a good one.
