Ferry firms DFDS and P&O Ferries have apologised for the long wait times of up to six hours at UK border controls on Saturday.
Families were stuck in cars in Calais for while returning from mainland Europe ahead of the new school year starting for many in England this week.
P&O Ferries added extra vessels for passengers who had missed their booked sailings, to “help with the passengers that have been stuck at border control”, as queues continued into the evening.
DFDS said queues could reach two and a half hours at border controls on Sunday.
A spokesperson earlier told BBC News: “Calais was affected by ‘the perfect storm’ of summer volumes in combination with post-Brexit border checks, causing six hours of queuing.
“We worked together with partners to reduce the queues as quickly as we could.”
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