HGV drivers crossing the Channel must continue to provide proof of an authorised negative coronavirus test within 72 hours of travelling to the border, according to the government.
It has urged hauliers to seek tests at one of 34 information and advice sites across the country before reaching Kent, in order to help smooth traffic management.
The testing arrangements will continue following a decision by the French government on 7 January to keep the current system in place.
It means drivers - as well as crew of HGVs and van drivers - planning to cross the Channel to the continent should get a negative test before reaching any crossing points.
Laura Hadzik, solicitor at Backhouse Jones, said: "If you don't have a test when you get to Kent, you will still be able to obtain one, but you will no doubt experience significant delays if you wait until you get to Dover."
While the military was involved in delivering tests in Kent last month, the government said hauliers must now get their test done before reaching the county instead.
Transport Secretary Grant Shapps said: “To help make this possible we are offering support to businesses to set-up testing facilities at their own premises, assisting the smooth passage of trucks and goods across the border, as well as setting up testing at information and advice sites around the country.”