Dover officials said the crisis had been escalated by the French seriously undermanning Eastern Docks control booths as Saturday, with 10,000 cars expected during the day, started with only three out of seven inspection booths open and a single French official dealing with a stream of coaches.

P&O Ferries, running six vessels to Calais described the situation as 'totally unacceptable' while DFDS with three ferries running to Dover and the same number to Dunkerque, were just as badly affected. Dover Port Authority said it has no authority over French operations but had raised staffing issues with the British Government last week.

The additional checks are a French response to terrorist attacks in Europe and as traffic tailbacks stretched 12 miles from the port on several major roads, Kent Police, Coast Guard staff and volunteers handed out bottles of water to motorists stuck in queues for more than eight hours.

The traffic backlog also affected people trying to reach the Eurotunnel terminal near Folkestone.