The M20 will be closed tonight for the installation of a controversial 50mph contraflow ahead of the Christmas break.

Operation Block will be deployed between Ashford and Maidstone overnight, closing the motorway in both directions from 8pm to 5am.

Once in place, the coastbound carriageway will be for EU-bound freight traffic only, with all other vehicles using the contraflow on the other side.

A 50mph limit will be in place until it is lifted on Sunday, December 22.

Operation Brock allows lorries to queue on the motorway in the event Dover Tap - a traffic management system closer to the port - fills up.

The contraflow will stretch from Junction 8 for Leeds Castle to Junction 9 at Ashford.

Two lanes of the London-bound carriageway will operate in each direction with a temporary barrier dividing the road.

When it is withdrawn later in the month, the M20 will again be closed overnight.

The decision to deploy Brock has been criticised by Ashford’s MP due to the inconvenience it causes his constituents. Sofan Joseph says he hoped port bosses could cope with Christmas traffic without having to resort to “emergency measures”.

But Kent County Council (KCC) says the Kent and Medway Resilience Forum (KMRF) says the contraflow is being put in place as a precaution because cross-Channel bookings appear busy in the run-up to Christmas.

The Port of Dover and Eurotunnel are both forecasting their peak tourist traveller numbers between December 19-21 with the majority of schools breaking up for the festive holidays. Bad weather could also cause delays.

Meanwhile, a permit scheme will once again be in place as lorries start to be filtered down to the port from the M20.

This means lorries without a permit will not be granted entry to the Port of Dover, which significantly reduces the number of truckers attempting to jump the queue and avoid the restrictions.

Freight vehicles heading to mainland Europe are legally required to follow the signed HGV routes to the Port of Dover and Eurotunnel, using the M20 and A20.

KMRF Operation Brock strategic lead, Simon Jones, said: "The indications from Eurotunnel and the Port of Dover are that we will see some really busy days in the run-up to Christmas, and we need to act on that intelligence and use all the facilities available to us, such as Operation Brock and TAP to minimise disruption.

“Our plan is to purely cover the peak period with the Brock implementation and if there are no further predicted issues, it will be removed again before Christmas.

“Our priority is to ensure everyone is able to get to where they want to go safely and as quickly as possible and to enjoy the festive period.”

Last week when this latest launch was announced, Ashford MP Sojan Joseph (Lab) told KentOnline he was “very disappointed”.

“I would have hoped that the Port of Dover would have been able to cope with the amount of traffic over the Christmas period without having to resort to emergency measures,” he said.

“I know what an inconvenience Operation Brock is for my constituents so I will continue to work with all the relevant agencies to find a workable solution for this issue.”