ICG, the company that owns Irish Ferries, has announced disruption to the Dublin/Holyhead route.
The Ulysses ferry, which brings passengers from Dublin to Holyhead, will be out of action for the next week or two. There has been no return date confirmed for the ferry.
The vessel had already been out of action since the beginning of the month. ICG released a statement on Monday morning confirming that it would take longer than expected for the ferry to resume its duties.
"We have now been informed by service engineers that the issue is more serious than originally anticipated and they expect the vessel will be out of service for a further period of one to two weeks," the company said in a statement.
The vessel has been in drydock in Belfast since June 28.
The company also clarified that it would make changes to the schedules of its other ferries in order to minimise the disruption caused to customers.
