Tourists hoping to travel to France have been told to expect a third day of disruption as the Eurotunnel was hit by long queues of traffic trying to get to Dover.
Passengers hoping to cross the Channel on Sunday were told to expect delays of at least two hours due to miles of queues to get to ferry terminals.
A day after authorities declared a critical incident in Dover, officials were handing out food and water to those stranded on the way to Folkestone Junction.
National Highways warned holidaymakers traveling to France to expect severe delays in Kent on Sunday.
Around 600 lorries were parked on the M20 as part of Operation Brock, which is designed to keep non-goods traffic moving when there are disruptions to travel across the Channel.
Jack Cousens, the AA’s head of roads policy, said Folkestone would be the focus of disruption on Sunday due to the aftermath of the “bumper-to-bumper” chaos at Dover.
Two of the main roads to the Eurotunnel, the A259 and A260, were blocked at 10am on Sunday as thousands of passengers headed for France at the start of the summer school holidays .
Cousens told Sky News: “We’ve had lorries piled up as part of Operation Brock on part of the M20 and the diversion back onto the A20 – they’re now at the terminal at junction 11a and that’s causing congestion
“Our concern is that the Eurotunnel will now be the main congestion problem, especially in the south-east.”
People reported sleeping in their cars overnight as delays averaged around six hours on Saturday, although some waited much longer.
Andrew Dyer-Smith and his family, who are on their way to France for their summer holidays, spent 21 hours in traffic on the roads around Folkestone. “We got to Folkestone at 9am yesterday to catch a 10.30 train and then we’ve been slowly crawling along for the last 21 hours,” he told the BBC.
Thousands of lorries queue near Dover amid travel chaos – video
Natalie Chapman, from hauliers group Logistics UK, said some lorry drivers had waited to cross the Channel for “more than 18 hours” in queues without toilets.
The disruption sparked a war of words on both sides of the Channel, as British authorities accused their French counterparts of understaffing the border, while politicians in Calais blamed Brexit for the extra checks.
The Port of Dover said it had processed 72,000 passengers, more than 200 miles of tourist and freight traffic, since Friday. His partners worked around the clock, he said, to clear “huge volumes” of vehicles overnight Saturday.
He added: “However, we shouldn’t have been in this situation in the first place.”
Doug Bannister, the chief executive of the port of Dover, previously blamed French border control officials, the Police aux Frontières, for failing to adequately staff passport booths, a charge denied by the French.
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Only four of the nine booths for French border controls for travelers leaving the UK were reported to be staffed on Friday morning, which port officials say led to the delay.
On Sunday, Bannister thanked commuters and city residents for their understanding “during this difficult period.”
He added: “I am incredibly grateful to everyone who has turned this situation around, from the French and UK authorities to our ferry operators, partners in Kent and our own port staff.”