The action follows the winding-up of the stevedore company, SMM, last month.
The Condor Rapide services between Jersey and St Malo on Friday, Saturday and Sunday have been cancelled.
The weekly Commodore Goodwill freight round trip between Portsmouth, the islands and St Malo will also not operate.
Elwyn Dop, Condor’s executive director of operations, said: ‘The situation is quite simply unacceptable. The ongoing disruption is hugely frustrating for passengers, freight customers and also our St Malo team.
‘We had considered using alternative ports in order to offer a service between the Island and mainland France, such as via Cherbourg, but this is no longer an option available to us due to the threat of a blockade there too.’
Condor’s freight and passenger teams are in contact with all customers affected to offer alternative arrangements while the company works with the French authorities to resolve the situation as quickly as possible.
