All planned summer sailings by the €150 million Irish Ferries boat the WB Yeats have been cancelled.
The ferry had been due to begin trips between France and Ireland at the end of July.
However, that will not go ahead as planned due to further delays in the delivery of the ferry from a German shipbuilder.
Around 6,000 bookings will be affected.
W.B. Yeats - Important Customer Update
— Irish Ferries (@Irish_Ferries) June 12, 2018
Irish Ferries said the cancellations are the result of 'extraordinary circumstances beyond its control'.
It said in a statement: "Irish Ferries is contacting affected customers this afternoon to inform them of the cancellations, offer them alternative travel options, and apologise for the disruption to their travel arrangements.
"If alternative travel arrangements do not suit, customers will, of course, be entitled to a full and immediate refund of all monies paid."
Affected customers will also be offered a €150 voucher for use on the company's Ireland-France routes next year.
The WB Yeats is now due to begin sailing on the Dublin - Holyhead route from September.