DFDS has told passengers booked to travel on its ferry service between Jersey and Guernsey that the company's planned sailings have been cancelled.
The Danish ferry operator says it follows "discussions regarding the proposed summer inter-island timetable".
DFDS had planned inter-island sailings, but that required the agreement of authorities in both Guernsey and Jersey.
In April, Guernsey's States rejected proposal to operate the Stena Vinga on the route outbound to Guernsey on Friday evenings, with a Monday return.
The Economic Development committee said the schedule presented 'material operational and resourcing challenges to Guernsey Ports and Customs and Immigration' as the Friday arrival would fall outside of the standard operating hours.
It also said it did not 'align with the principles of reciprocity'. Brittany Ferries - Guernsey's chosen ferry operator - runs a day return service from Guernsey to Jersey on Wednesdays.
DFDS says, following that decision, 'the inter-island sailings currently scheduled for the summer period have been withdrawn from sale'.
Customers affected will be offered refunds.
A statement said:
"While the sailings will not proceed at this stage, DFDS said it remained open to further discussions regarding future inter-island connectivity and continued to believe there was value in improving links between the islands.
"The company added that it would welcome further engagement involving both island governments, ports and other relevant officials."
DFDS says it will use the Mondays in July and August that it would have served Guernsey to put on extra services to St Malo instead.
The additional dates are 6 and 20 July, together with 3, 17 and 24 August.
There will also be an additional sailing on 2 July in response to demand from people travelling to the Le Mans 24 hour classic historic motorsport event.

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