Ferry company Stena Line, which has cut journeys from Northern Ireland to England and Scotland, is lobbying the Executive and London for support for its remaining services.
The Irish government has announced a support package which will benefit some Stena Line routes in the Republic, such as Dublin to Holyhead, Rosslare to Fishguard and Rosslare to Cherbourg. The €15m (£13m) emergency package is aimed at keeping supply lines open during the coronavirus crisis.
Stena Line this week said it is temporarily laying off 650 staff and making 150 redundant, as well as cutting journeys, to cope with a fall-off in business.
The company employs a total of 950 staff on its sailings from Northern Ireland to Liverpool, Heysham and Cairnryan. However, it's not clear how many will be affected by the cuts. It has a total workforce of 1,650 on the island.
But it has cut capacity on its Belfast to Liverpool route from six crossings daily to four, while Belfast to Cairnryan is down from 12 to 10. It said it had to cut positions in order to maintain its role as a freight carrier, and continue to carry passengers on essential journeys. Ticket sales on passenger ferries help cover the costs of freight services.
But a spokesman for the company said it is now lobbying both the Executive and the Department for Transport in London, which is understood to be working on possible support for the maritime sector.
A Department for Transport spokesman said: "We recognise how challenging this period is for the Transport sector and encourage all firms to make use of the further changes to business support, announced by the Chancellor, helping make funds easier to access for more companies.
"We're committed to working with industry leaders and devolved administrations, to offer the support they need and help provide certainty for workers. We will continue to directly engage maritime companies and associations to tackle these challenges."
Stena Line confirmed Paul Grant, trade director for Irish Sea and North Sea routes, had written to the department in London and the NI Assembly pressing the need for support.