Ferry trips between Mostyn Docks in Flintshire and Dublin are being stopped by P&O - just 18 months after the company pledged their support to the redeveloped dock.
Ferry crossings were switched to Mostyn from Liverpool
The port of Mostyn was reopened with a passenger terminal in February 2001 following a £17m facelift and the security of a brand new contract from ferry operator P&O.
The shipping company pledged their support to Mostyn and the local economy by switching its Irish Sea crossings from Liverpool to Mostyn two years ago.
At the time the ferry operator said Mostyn was an "ideal location".
However, P&O's announcement on Tuesday to sell its routes and vessels at the ports of Liverpool, Fleetwood and Dublin to Stena Line has now left Mostyn without a ferry company to take passengers between north east Wales and Ireland.
Twenty six P&O workers will be made redundant at Mostyn Docks under the deal which could take up to six months to complete, it was announced on Tuesday.
The actions of P&O in shutting this excellent facility so soon after it had opened defies belief
Stena Line have confirmed that they have no plans to buy the Mostyn route.
P&0 spokesman Stuart Walker said the company was "disappointed" with the situation in Mostyn.
"We needed to provide a regular timetabled service which hasn't been possible because of the dredging situation," he said.
"We've not been able to make the route profitable."
Delyn MP David Hanson condemned the announcement.
"The actions of P&O in shutting this excellent facility so soon after it had opened defies belief," he said.
"This decision is bad news for Flintshire but also for P&O in losing such an excellent facility and workforce."
Mostyn Docks cost £17m to redevelop
First Minister Rhodri Morgan officially opened Mostyn Docks, which employs 120 people in total, in February 2001.
Apart from the ferry services, the port of Mostyn also deals with cargo handling operations.
A spokesman said P&0's decision to drop its Irish Sea passenger services from there will not affect the port's employees.
Bosses at Mostyn Docks plan to transport wings made at Airbus in nearby Broughton for the A380 superjumbo by boat to Toulouse in France.
Flintshire Council Leader Alex Aldridge said he remained optimistic about Mostyn Docks' future.
"It will remain a key port facility," he said.
"I'm looking forward to the day that we see the wings of the A380 go from here."
The port said it would now try to secure a new operator for the P&O terminal.
The transformation of Mostyn Docks was made possible with a £17m investment under the Welsh Assembly's Regional Selective Assistance grant aid.