Operation Brock, the Government's contingency plans to manage lorry traffic in Kent, could take up to 14 days to implement raising concerns of traffic chaos in the event of no Brexit deal.
A Freedom of Information request from the Guardian revealed that Operation Brock would not be automatic. There would need to be a decision to 'activate' the policy and then steel barriers would need to be installed to make a planned contraflow system on the M20 safe for ordinary vehicles.
Highways understands that up to two weeks is the current planning yardstick and so it is likely to be shorter. If the UK were to face no deal scenario a decision to activate would need to be made by mid-March at the latest for it to be in full operation by Brexit day 29 Mar 2019.
If Brexit negotiations go to the wire, the contingency plans might not be put in place until April leaving the Port of Dover and Kent's motorways facing chaos.
Highways England - the strategic road operator - and the Government developed Operation Brock following the difficulties over Operation Stack, which saw parts of the M20 turned into a lorry park.
The policy, which unlike Stack uses a contraflow to keep the roads open when problems arise, is not just for Brexit but is a contingency measure that would be used if needed for other scenarios.
Highways England said: 'We currently estimate it will take up to 14 days to initially bring the M20 junction 8 to 9 temporary solution into action, once the decision to activate it has been taken.
'This duration is due to the one-off installation of [a] temporary steel barrier and the traffic management signs. We are developing plans that may enable faster deployment using alternative barrier types, this of course is dependent on a safe and suitable method being found.'