The port of Dover has been closed to all vehicle traffic leaving the UK for the next 48 hours.
France acted to halt lorry movements in the wake of fresh concerns over the spread of a new strain of coronavirus.
UK ministers and officials will discuss the move at the government’s Cobra emergency committee on Monday.
Freight from coming to Britain from France will be allowed, but there are fears lorry drivers will not travel to avoid being stuck in the UK.
Transport Secretary Grant Shapps urged the public and hauliers not to travel to ports in Kent, including Dover. “We expect significant disruption in the area,” he said.
The Port of Dover is closed to traffic leaving the UK “until further notice” due to border restrictions in France, port authorities said in a statement.
“Both accompanied freight and passenger customers are asked not to travel to the port,” it said. “We understand that the restrictions will be in place for 48 hours from midnight.”
About 10,000 lorries a day travel between Dover and Calais during peak periods such as Christmas.
Border restrictions could mean disruption to food supplies, as well as difficulties in meeting orders of British goods in continental Europe.
“Tonight’s suspension of accompanied freight traffic from the UK to France has the potential to cause serious disruption to UK Christmas fresh food supplies – and exports of UK food and drink,” Food and Drink Federation (FDF) chief executive Ian Wright warned.
“Continental truckers will not want to travel here if they have a real fear of getting marooned.
“The government must very urgently persuade the French government to exempt accompanied freight from its ban.”
Freight industry lobby group Logistics UK said it was concerned about the welfare of drivers going from the UK to France, and said they should have access to regular testing.
It appealed for calm from shoppers, and said it was “maintaining close contact with UK government to ensure that supplies of fresh produce are available throughout Christmas and the new year.”
The British Retail Consortium (BRC) joined the FDF in appealing to the government to find a solution, but also added that there should be no immediate shortages.
“Retailers have stocked up on goods ahead of Christmas which should prevent immediate problems,” the BRC said.
While the situation will be discussed at the government’s Cobra emergency committee on Monday, meetings are being had between ministers and officials on Sunday night, according to BBC political correspondent Nick Eardley.
He added that the government does not think the restrictions will affect the delivery of Covid-19 vaccines to the UK.
Scotland’s First Minister Nicola Sturgeon has called on the government to extend the Brexit transition period as it deals with the new coronavirus variant, saying it was a “profoundly serious situation” which “demands our 100% attention”.
The current transition period is due to expire at the end of the year and the EU and UK are still negotiating a trade deal.
Without it both sides will have to collect expensive tariffs that the Office for Budget Responsibility says could harm the UK’s economy.
French transport minister Jean-Baptiste Djebbari said France was suspending all traffic from the UK from midnight for at least 48 hours.
A number of countries have banned or are considering stopping flights from the UKfollowing the emergence of a new variant of coronavirus.
Ireland, Germany, France, Italy, the Netherlands and Belgium are all halting flights, and other nations are considering the move.
Trains to Belgium are also not operating.
Eurotunnel is suspending access to its Folkestone terminal from 22:00 GMT for traffic and freight heading to Calais.
Coronavirus cases in the UK have risen by 35,928 – nearly double the number recorded last Sunday, figures show.
Public Health England medical director Yvonne Doyle said the “sharp” rise in cases was of “serious concern”.
It comes as Health Secretary Matt Hancock warned that the new variant of the virus was “getting out of control”.