Holidaymakers still face long waits to cross Channelwhile trucks remain backed up after a second day of travel chaos.
Additional post-Brexit border checks and French insufficient staffing of checkpoints by the authorities Dover accused of theft.
Scenes of closed roads and cars seen on Friday were repeated on Saturday as thousands of commuters faced long queues and some truck drivers waited more than 18 hours.
This comes at one of the busiest periods for overseas travel from the UK, as most schools in England and Wales are out for the summer.
The foreign affairs and leadership secretary, Tory leadership hopeful Liz Truss, said the disruption at the port of Dover was the fault of the French authorities when asked if Brexit was the cause of the transport chaos.
Making a pre-election visit to Kentshe said: “This is a situation that has been caused by a lack of resources at the border.
“And that’s something that the French authorities have to decide, and that’s something that I’m very clear with them.”
But French politician Pierre-Henri Dumont, a Republican member of parliament for Calais, blamed Britain’s exit from the EU, telling BBC News it was “post-Brexit”, with more checks needed, and claiming the port at Dover was “too small” and too few stalls due to lack of space.
Passengers sailing across the English Channel from Dover must go through French border control before boarding the ferry.
The port authority said it was “relieved that French border personnel (Police Aux Frontieres) are now fully mobilized at the French border control in Dover”.
Port of Dover chief executive Doug Bannister said it was “very disappointing” to be “let down” by poor resources at the French border and said there would be “increased transaction times” at the border due to the need for extra checks.
He later said he welcomed the “commitment shown by the French and British authorities to resolve the issue”, adding that the necessary staffing levels should be maintained until the end of the summer.
Natalie Chapman, from carrier group Logistics UK, echoed concerns about French staff numbers and Brexit-related changes.
She said: “As I said, the reason was the lack of resources yesterday, but also of course the traffic is taking a lot longer to process than before.
“Before Brexit you just waved your passport and they might or might not be looked at, but now everyone is checked and stamped.”
Holidaymaker Angie Emrys-Jones and four family members, including three children, queued for almost 11 hours and were only able to board the Eurotunnel at 4.15pm – they had queued at 5.30am.
The 46-year-old from Cornwall said the family were “full” and faced a 16-hour journey to Umbria, Italy.
While those queuing to cross the Channel still faced three to four-hour waits around 5pm, congestion on many routes in the south-east was cleared, the AA said.
An AA Route Planner traffic warning was still issued for holidaymakers heading towards the Port of Dover and the Eurotunnel terminal in Folkestone, while the backlog of goods still needed to be cleared.
However, the AA predicted that the roads would be much quieter on Sunday.