The firm that employs Belfast City Airport's baggage handlers and check-in staff is planning to cut 4,175 jobs across the UK, it has emerged.
GMB and Unite represent Swissport workers, who handle flights coming into nearly every regional airport in the UK, and described the news as "devastating".
It is understood that 112 Swissport jobs at Belfast City Airport are at risk.
The UK's aviation industry has been hit hard by the coronavirus lockdown, which has been in place since March and resulted in several airlines making redundancies due to the majority of flights being grounded.
Airlines have only began restarting routes in recent weeks, however it will be some time before full schedules resume.
Before the lockdown was imposed, however, Swissport started a 30-day consultation on plans to make 95 workers at Belfast City Airport redundant.
On Wednesday, Swissport chief executive Jason Holt said the company has to reduce the size of its workforce to survive.
Mr Holt said in a message to staff: "We must do this to secure the lifeline of funding from lenders and investors to protect as many jobs as possible in the United Kingdom and Ireland.
"It's true that we've seen tough times before - volcanic cloud, 9/11, the financial crisis - and we've weathered these. But this time it's different. We have never seen anything like Covid-19 in our lifetimes.
This is a hard decision to make, but immeasurably harder for our colleagues to hear. But it’s an essential decision if we are to keep operating and to protect as many livelihoods as possible in the long run.Jason Holt, Swissport chief executive
"We are now facing a long period of uncertainty and reduced flight numbers, along with significant changes taking place to the way people travel and the way goods move around the world. There is no escaping the fact that the industry is now smaller than it was, and it will remain so for some time to come."
In a further statement, Mr Holt said he expects around half of Swissports 8,500 workforce will be made redundant.
"I want to stress that this isn’t in any way a reflection on the dedication of our teams and the quality of their work. The situation we’re facing is one shared by the whole industry. These are very challenging existential times," he added.
"This is a hard decision to make, but immeasurably harder for our colleagues to hear. But it’s an essential decision if we are to keep operating and to protect as many livelihoods as possible in the long run.”
The latest news has increased calls for the UK Government provide financial support for the aviation industry to save jobs.
Nadine Houghton, GMB national officer, said: “This is devastating news. At least 4,000 workers - and possibly many more - will lose jobs which are essential to regional economies.
"With Swissport now considering job cuts on this scale we have deep concerns about the viability of many of our regional airports and the benefits for regional connectivity that they bring.”
Oliver Richardson, Unite regional officer, said time is running out to save jobs.
“We can’t wait any longer, the UK Government needs to urgently intervene with a bespoke financial package and an extension of the 80% furlough scheme for the aviation industry," he said.
“Speed is of the essence if the Government is to save thousands of aviation jobs and livelihoods. It’s not too late.”
Belfast City Airport has been approached for comment.