Food producers in Britain warned that perishable goods exports were losing their value because congestion around the port of Dover caused by disruption to ferry services and customs operations.
A number of issues have converged to cause difficulties at Dover, the main route for road freight to mainland Europe.
P&O Ferries, which previously accounted for a third of capacity at Dover, suspended operations last month.
There have also been technical problems with the government customs website which processes export procedures since Brexit.
A fresh meat exporter said failure to supply means losing EU export customers, who turn to other countries to provide a more reliable supply.