There are fresh fears that Kent’s roads could be gridlocked on ‘Day One’ of a no-deal Brexit after leaked documents reportedly warned of a two-day delay at Dover.

An analysis, commissioned by the Department for Transport (DfT) has suggested the worst case scenario would be a two-day maximum delay for freight and vehicles at the port and an average wait of one-and-a-half days.

The prospect of such a delay could see some 8,000 vehicles stacked on the county’s roads, the report is said to have claimed.

If accurate, that could see the Manston airport site brought into use as an emergency lorry park. It is on standby under the contingency plan for Kent known as Operation Brock and would be brought into use if capacity for lorries on the M20 was exhausted.

The warnings have been raised in documents leaked to Sky News and echo concerns about disruption and delays in a previous leak of the details of the government’s contingency plans under the code name Operation Yellowhammer.

According to Sky, even with a best case scenario, with businesses as prepared as they possibly could be, vehicles will be waiting for two to three hours, with 50% of vehicles waiting for at least eight.

The leaked copy of Operation Yellowhammer said the government said the flow of freight could be reduced by as much as 60% within one day.

That would result in “ significant queues” in Kent with lorries facing a maximum delay under a reasonable case scenario of two and a half days before being able to cross the border.

Cllr Rob Bird, the opposition Liberal Democrat leader on Kent County Council, said: “This latest leaked report shows just how catastrophic a no-deal Brexit would be for Kent and for the UK as a whole. The problems at Dover and at the Channel Tunnel will have serious implications for much of the county, with the M20 and many other main roads seized up."

But Dover MP Charlie Elphicke dismissed the report as another example of Project Fear. “Of course it’s vital that our borders remain open, secure and free-flowing after Brexit. As everyone knows, Boris Johnson is working day and night to make sure we take full advantage of the Transit Convention, meaning there need not be any checks at either Dover or Calais under European law. The truth is that whatever happens Britain will be a massive success after Brexit – and our best days are yet to come.”

Eurotunnel said plans it had ready for the original March deadline remained in place. Spokesman John Keefe said: "We have worked intensely with the customs authorities to build an offline inspection facility with 100 spaces. This will ensure controls do not interfere with the normal rate of flow through the Tunnel. All of this was ready for 29 March. Any vehicles without the correct paperwork will be filtered out of traffic by the authorities upstream, on the motorway network. Eurotunnel is confident that it is ready for Brexit, whatever the outcome”.

The latest warnings come as the government launched a £100m public information campaign urging people to make sure they are prepared for Britain's departure from the EU.

The PR blitz will involve billboard advertising as well as public information adverts on TV and radio.

The Department for Transport has been asked to comment but has yet to do so.

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