Safety measures will be added to the smart motorway section of the M20 nearly a year after it was opened.

Work on transforming a 6.5-mile stretch of the M20 between junction 3 at West Malling and junction 5 at Aylesford, where the hard shoulder became a live lane, was finished in April.

Throughout this time it has been operating without 'stop vehicle detection units', devices which use radio waves to spot a stationary vehicle and quickly alert control room staff of the emergency.

Now it has been announced work to install the system on the M20 will start on Monday, January 4 and will be completed by the end of March, with overnight closures in place.

However, Highways England has warned its plans could alter, "depending on the changing situation in Kent".

This, it is believed, refers to the predicted disruption on the M20 and nearby roads caused when the Brexit transition period ends this Friday.

Chatham and Aylesford MP Tracey Crouch argued in January that the smart motorway should not open without the safety measures.

In April, she expressed her dismay that the "potentially life-saving" equipment might not be operational for three years.

Reacting to the latest news, Ms Crouch said on her Facebook page: "While I don't believe this is anywhere near as good as a hard shoulder, no "smart motorway" in my view should be operational without them.

"There will be some disruption to the network and, I am afraid, to constituents alongside the motorway as they are installed.

"I know you have suffered enormously from years of continuous overnight works and this will inevitably be distressing to hear of yet more works but they have explained some of the mitigating actions they will be taking and I will hold them to account on this."

Smart motorways use technology to sense traffic flow and set speed limits accordingly.

"Although the work... is scheduled to start on Monday, January 4 we stand ready to change our plans, depending on the changing situation in Kent."

The design for the M20 involved converting most of the hard shoulder permanently to a traffic lane to create extra capacity.

Concerns about accidents and safety were raised after figures showed there had been 38 deaths on smart motorways in five years.

In 2017, Steven Godbold was hit and killed by a lorry on the M25 near Sevenoaks.

A Highways England spokesperson said: "Although the work to install stopped vehicle detection on the M20 in Kent is scheduled to start on Monday, January 4 we stand ready to change our plans, depending on the changing situation in Kent.

"The work is planned to take place overnight only and to be complete by the end of March 2021."

Most of the upgrade work will be carried out overnight from 8pm to 5am, using temporary lane closures with all restrictions removed during the day.

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