The Dover border crisis means the UK will see disruption to supply chains as “never experienced” before, freight and industry chiefs have warned.
Ministers are scrambling to agree a deal with France to open the border after Paris closed the port amid fears about the new and more infectious strain of Covid-19 found in the UK.
Bosses told MPs on Tuesday that as many as 4,000 lorries are backed up in Kent and “at various points” elsewhere.
The emergency has sparked widespread concern there may be shortages of some foods.
French president Emmanuel Macron shut the border on Sunday after Boris Johnson’s snap press conference in which the prime minister introduced strict new measures for London and huge swathes of the south-east.
But Duncan Buchanan, director of policy at the Road Haulage Association, predicted the worst may yet be to come.
Lorry drivers will be left grappling with new regulations from January 1 when the Brexit transition period ends.
Buchanan told MPs on Parliament’s business and industrial strategy committee: “This is a very serious problem – whether you have moved trucks from one place to another, it is irrelevant.
“This is a very different level of supply chain disruption, of the like we have probably never experienced.
“Many of the retailers are saying that [...] we will be fine until Christmas at least, but we must recover very fast to keep the shops fully stocked after Christmas. It’s a big worry.”
Ian Wright, chief executive of the Food and Drink Federation (FDF), meanwhile, said the “number of trucks that need to be cleared as this unwinds will be more than 4,000”.
He also said UK exports will also be affected, including Scottish seafood products.
“There are dozens of lorries there with product that is going off. There is a huge hit here to Scottish seafood,” he told MPs.
“The government was well aware of the power of the announcement it made on Saturday. [...]
“Everyone would have rightly known that everyone in Europe would have reacted this way, and in fact we felt similarly when Danish mink were infected.
“The consequence of this is the chaos we’ve seen over the past 24 hours. It’s incumbent on the government to come forward to compensate those who have lost out because of that failure of authority.”
Andrew Opie, director of food and sustainability at the British Retail Consortium (BRC), said the next 24 hours would be crucial.
He said: “The real issue we face is what happens in the next day or so.
“If we do not see the empty trucks, which have already delivered warehouses and stores, getting back over the Channel, they will not be able to pick up the next consignment of fresh fruit, vegetables, salad vegetables, all the food we do not grow in the country at this time of year.
“What we’ve been told by members is that unless those trucks can start travelling again and go back to Spain and Portugal and other parts of Europe, we will problems with fresh produce from December 27.
“What we need is for those trucks to move in the next 24 hours if we are to avoid seeing problems on our shelves.”
The European Commission recommended an EU-wide approach that would allow essential travel, and transit of passengers from the UK.
Flight and train bans “should be discontinued given the need to ensure essential travel and avoid supply chain disruptions”, the commission said.
France and the UK have yet to reach an agreement, however, though it is thought the UK hopes a facility offering rapid tests could reassure Macron.