Traffic management measures introduced in preparation for a no-deal Brexit will be suspended, the Government said.
Operation Brock came into force in Kent at 6am on Monday, three days before the UK was due to withdraw from the EU.
But the scheme will be ended “as soon as possible” after a further delay to Brexit was confirmed, a Department for Transport spokeswoman said.
Lorries heading for Europe face a 30mph speed limit on a 13-mile stretch of the coastbound carriage of the M20 as part of Operation Brock.
All other traffic on the motorway, including lorries carrying out UK deliveries, must use a 50mph contraflow of two lanes in each direction on the London-bound side of the road.
Motorists are being warned to allow for extra travel time and to make sure they have food and water in their vehicles in case of delays.
Several holding areas to park lorries have been made available if required, including at Manston Airfield.
The measures are aimed at minimising disruption and keeping local traffic moving.
Operation Brock was initially deployed on March 25, four days ahead of the first planned Brexit date.
It was deactivated around three weeks later following the delay to the UK’s withdrawal from the EU, but the steel barriers for the contraflow system and 50mph speed limit remained in place.