Aer Lingus is to commence negotiations with unions representing staff at the airline about cuts of up to 900 jobs.
It is understood that at a briefing this morning, union representatives were told that in order to cut costs across the board, the company is seeking to reduce its 4,500-strong workforce by up to 20%.
The timing of the cuts will depend on the outcome of further consultation with unions over the next few weeks.
So far it is not yet clear which jobs, routes or services will be targeted in the cutbacks.
Fórsa, which represents staff at Irish airlines, airports and airport authorities, has called for swift Government intervention to ensure Ireland has an aviation industry once the coronavirus emergency is over.
The union said there was a danger that the industry would be so weakened over the coming months that it would be unrecognisable by the end of the year, with regional airports particularly vulnerable.
Indications of a continuation of the state wage subsidy scheme until after-May was an important first step in underpinning the sector, Fórsa said.
The union said it is expecting specific proposals from Aer Lingus management next week on its cost-cutting plans.
"We've sought that pay arrangements currently in place be extended until 21 June as a minimum," said Fórsa's head of Services & Enterprises Angela Kirk.
"We pointed out that the wage subsidy scheme was of considerable financial benefit to the company and the extension of the current arrangements until that date is affordable.
"We're awaiting proposals on what we expect to be a voluntary redundancy package, and we've told the company that there will need to be discussions on any proposed changes to work practices and working time."
Fórsa said it also expects to engage with Ryanair in the coming days.
Earlier today, Ryanair said it could take at least two years for passenger demand to return to normal and this could result in up to 3,000 jobs losses, mainly among pilots and cabin crew.
A month ago Aer Lingus halved the working hours and pay of staff because of the reductions in capacity and passenger travel due to the coronavirus.
It warned back then that if the operating schedule reduced further, or if full grounding of operations was required, there would be a necessity for further measures.
It is understood that the job cuts being sought by Aer Lingus will be via a voluntary redundancy scheme.
Aer Lingus would not comment on the situation, saying only that it is continuing to communicate directly with its employees and engage with their representative bodies.
Its parent company, International Consolidated Airlines Group (IAG), which also owns British Airways, along with Spain's Iberia and the low cost Vueling carrier, said on Tuesday that its operations lost €535m in the first three months of the year.