CORONAVIRUS and Brexit uncertainty have been cited among reasons for the suspension of weekday services by the Carlingford Lough Ferry.
Sailings of the cross-border service between Greencastle on the northern side of the lough and Greenore in the Republic will be reduced from September 28.
There will only be weekend and holiday services until March 26 2021, with the company saying the predicted number of passengers was "not sufficient" to maintain daily crossings.
Full-week sailings will, however, take place during the Halloween and Christmas periods.
The roll-on roll-off service began in 2017 commercial director Irene Hamilton said: "We greatly regret the disruption that this will cause to our commuter customers who have supported our business since launch.
"While we have seen a growth in our weekday traffic during the wintertime, the overall volumes are not sufficient to justify a continuation of the service.
"We know from experience that the only way to grow traffic is by running the service and we realise that a cross-border commuter service will naturally take longer to develop, however, the added complications of Brexit uncertainty and Covid-19 have led us to this regrettable decision."