Holidaymakers have been warned the Port of Dover will be “very busy” again next weekend.
The chaotic scenes witnessed last Friday and Saturday, when travellers had to queue for up to six hours, have largely eased.
Vehicles were flowing freely today but a major incident remains in force.
However, Toby Howe of the Kent Resilience Forum said it was a “very vulnerable situation”.
Mr Howe said things were back to “business as normal” but remained “on a knife edge”.
He told BBC Radio 4’s Today programme the coming weekend was expected to be the second busiest getaway of the summer holidays and, with traffic crossing the Channel back to pre-pandemic levels and additional checks at the border since the UK left the European Union, it took “very little to cause those tailbacks”.
It came as the travel disruption extended to Eurostar services between Paris and London as a train was cancelled and British passengers remained stranded in France.
Those trying to get across the Channel on were braced for scenes of “bedlam”, with thousands crammed into overflowing departure lounges.
The 08.01 Monday morning Eurostar service from London to Paris was “cancelled for operation reasons,” Eurostar announced.
A train that was meant to be coming the other way – from Paris to London – was also cancelled on Sunday evening, because of a broken-down train on the line in France.
P&O Ferries said queues “picked up” this morning, and that it took an hour for passengers to clear French passport control.
A lack of French border force officials manning kiosks at the Port of Dover was largely blamed for the chaos late last week.
The situation was made worse, say critics, by greater passport checks in the wake of Brexit.
A spokesman for the Port of Dover said today: “The Port of Dover is pleased to report that traffic is flowing normally this morning.
Ferry operator DFDS told passengers that there were “queues of around an hour” for French border checks this morning, and to “allow a minimum of 120 minutes before your departure to complete all controls”.
Nearly 142,000 people travelled through the port over the weekend.
Downing Street insisted the chaos seen in recent days was not the result of Brexit.
Prime Minister Boris Johnson ’s official spokesman said: “We understand there are changes, post-Brexit.
“We recognise that, we have planned for that.”
They said the problems are down to a combination of factors “including a shortage of French border control staff.
“So these are not scenes that we think are necessitated by leaving the European Union,” the spokesman said.
“We think we have operational procedures and processes in place that do not need to see these levels of queues.”
