Delays of up to two-and-a-half hours at the port of Dover can be expected at the start of the summer holiday peak this weekend.
The warning was issued as motorists planning to take ferries to the Continent were advised not to arrive three hours ahead of their sailing.
Volumes are expected to peak on Friday when more than 8,500 cars are projected to pass through the port.
Car departures on Saturday are expected to reach 3,200 between 6am-10am and 2,400 between 10am and 2pm.
Port chief executive Doug Bannister told The Times: “When passengers arrive at the Port of Dover, they will be processed through border controls – anticipated to take around 90 minutes on peak days.
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“However, our modelling indicates that processing times may be up to two-and-a-half hours during the peak hours of 6am to 1pm during the first couple of Saturdays and Sundays of the summer holidays due to the extreme popularity of these days.”
Chief operations officer Emma Ward said the port was working with the French border force to ease bottlenecks.
She said: “If you miss your sailing, you will always get the next [available] one.
“So people do not need to worry about arriving too early. That’s what causes the bottlenecks. We don’t want people to arrive more than three hours before their crossing.”
The port blamed long processing times for delays for some coach passengers of more than 14 hours at Easter.
Installation of an additional booth for French border officials is expected to be completed before Friday, and hour-by-hour traffic flow projections have been created.
A new system for processing coach passengers, involving advanced passenger information checks being carried out away from the main port during busy periods, is also yo be used.
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