RMT transport union members at Eurostar trains have voted by more than nine to one for industrial action.
They are fighting the firm’s failure to confirm that it will not implement a policy of lone working for train managers.
The RMT’s train manager members will now refuse to operate any passenger service that is not fully staffed with a complement of two qualified train managers.
This ongoing action will begin from Monday of next week.
They will also refuse to collect upgrade revenue from passengers on board trains on Monday of next week.