Trade groups have warned of disruption to food supplies following France's ban on travel from the UK.
France suspended all travel links with the UK, including freight, for 48 hours from midnight on Sunday 20 December.
The ban, enforced as a result of concerns over the new COVID-19 variant, means freight lorries cannot cross by sea or through the Eurotunnel, and the Port of Dover has closed to outbound traffic.
Freight coming to Britain from France is allowed, but there are concerns that lorry drivers will not travel to avoid being stuck in the UK.
Unaccompanied freight, such as containers or lorry trailers on their own, are permitted to be transported, but outbound vans, lorries and trucks are banned.