Aer Lingus and British Airways parent company IAG are poised to announce that they have finally agreed to a £1bn takeover of the Irish airline by a foreign consortium.
Any deal will now be dependent on getting the nod from the Irish government, which will meet tomorrow to discuss the takeover's implications.
The Aer Lingus board has reportedly accepted a third and improved proposal from International Airlines Group (IAG).
IAG, which owns the Spanish carrier Iberia as well as British Airways, has been seeking a deal with Aer Lingus to gain access to its valuable take-off slots at Heathrow Airport and to develop Dublin as a secondary hub for transatlantic flights.
Aer Lingus is the fourth busiest operator at London's Heathrow behind British Airways, Lufthansa and Virgin Atlantic.
It flies up to 12 times daily between Belfast City and London Gatwick or Heathrow. Other routes from Belfast include Malaga, Faro and Palma.
British Airways also offers Northern Ireland customers up to six flights a day from Belfast City Airport into London Heathrow.
IAG previously offered €2.30 a share and then €2.40 a share, but was rejected by Aer Lingus.
While the Aer Lingus name and livery will remain, control of the airline will move abroad; something that has led several government ministers to express doubts about the deal.
With a 25% stake, the Irish government has enough voting rights to prevent any takeover and the focus will now shift to tomorrow's Cabinet meeting where Transport Minister Paschal Donohoe will brief colleagues on the ramifications of the deal.
Mr Donohoe, who represents a north Dublin constituency with many airport workers, said yesterday that the Irish government will look at issues such as the slots at Heathrow Airport, and that job security at Dublin, Shannon and Cork airports will also be considered.
The acquisition of Aer Lingus would mark a bittersweet moment for IAG boss Willie Walsh who tried to buy Aer Lingus more than a decade ago as part of a failed management buy-out when he was chairman.
IAG was formed by former Aer Lingus pilot Mr Walsh when he merged British Airways and Iberia in 2011.
IAG employs more than 60,000 people. A restructuring programme at the previously loss-making Iberia has seen 2,500 staff leave under a voluntary redundancy scheme.
Currently, Aer Lingus directly employs 3,900 people, mostly in Dublin, with 2,100 of these described as ground staff in areas such as clerical, operative and back office roles.
Fianna Fail and the Impact union expressed fears that more than 1,000 jobs could be lost due to the acquisition.
Aer Lingus' fortunes have improved in recent months and under chief executive Christoph Mueller it reported the airline's strongest summer trading performance since the financial crisis, with operating profits up 19% to €112.9m (£88.m) in the quarter to September 30, 2014.
The airline carried nearly a quarter more long-haul passengers in the period than a year earlier while increasing its revenue per seat.
It plans to launch a new Dublin-to-Washington service in May and will also increase services on existing transatlantic routes.