U.K. firms desperate to maintain supply lines after France blocked truck traffic are looking at switching to cargo jets and freight trains to keep goods flowing.

J Sainsbury Plc and Tesco Plc are exploring all options to keep supplies flowing, including the use of planes for some fresh-vegetable shipments instead of truck ferries, while Deutsche Lufthansa AG may add dedicated freighter flights to the U.K. Eurotunnel, which operates the Channel Tunnel rail link between Britain and France, said talks are underway about running extra freight trains.

“There’s been a great deal of discussion with a number of companies contacting us, both existing customers and potential new ones,” Eurotunnel spokesman John Keefe said. “We’d already seen an increase in demand because of the Brexit deadline but there’s plenty of spare capacity.”

Trucks bound for the continent are lined up on the M20 motorway outside Dover, Britain’s busiest ferry port, after a new coronavirus strain prompted France on Sunday to bar drivers from crossing the Channel. The ban, which also applies to Eurotunnel’s truck shuttles, threatens to disrupt just-in-time supply chains and to create shortages of some foods and perishable goods.

Sainsbury said it’s exploring alternatives to trucks to keep its stores stocked with lettuce, cauliflowers, broccoli and citrus fruits from the Continent. Air-freight is an option, though the grocer hopes that France and Britain will reach an agreement to reopen links, spokeswoman Victoria Durman said.

Tesco, Britain’s biggest supermarket, has “plenty of food for Christmas,” said Shona Buchanan, a spokeswoman. But if the disruption continues beyond the next two days, “there may be reduced supply on a few items later this week.”

Grocers cannot stockpile perishable fresh produce, meaning regular replenishment of supplies is essential. Alternative supply routes being considered alongside air freight include the use of ferries sent directly from Spain and increasing stock from Holland and the U.K.

Dedicated Freighters

Lufthansa will continue to fly passengers to Britain unless there’s a ban on doing so, according to spokesman Helmut Tolksdorf. The aircraft will return to Germany empty, though, after it and others closed their borders to arrivals from the U.K. Operating a dedicated cargo service would help plug the gap should inbound flights to London, Manchester and Edinburgh also have to cease. Lufthansa Cargo operates planes including Boeing Co. 777Fs capable of carrying 100 metric tons.

Virgin Atlantic Airways Ltd. said cargo-only flights between Britain and Europe that use belly-space in Airbus SE A350 passenger jets currently surplus to requirements sold out this morning. The carrier is looking to add as many services as possible for Tuesday, spokeswoman Laura Brander said.

Chunnel Trains

Eurotunnel currently operates four or five dedicated freight trains a day, carrying bulk products including car parts, steel, aluminum and liquids. That compares with six shuttle trains an hour during normal times carrying trucks through the sub-sea rail route. Before the service was halted, traffic on those trains had increased 11% from a year earlier as companies rushed to stock up ahead of the Dec. 31 no-deal deadline.

Spokesman Keefe said freight services have seen a pickup in chilled foods sent to Britain from more distant parts of Europe as a result of earlier concerns about delays at Dover.

Running more trains through the tunnel would be a simple matter, he said, though securing pathways across Europe can take a few weeks in normal times. Channel Tunnel cargo services are operated by GB Railfreight and Deutsche Bahn AG’s DB Cargo.

Other options for offsetting the loss of truck traffic might including sending more goods in containers, usually the reserve of long-distance shipments from Asia. Felixstowe, Britain’s biggest container port, has been suffering delays and snarl ups of its own amid a surge in volumes from restocking before Christmas and the Brexit deadline.

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