Speed cameras are being installed in the Medway Tunnel as part of measures to improve traffic flow in and out of the Medway City Estate.

The work started on Monday with the tunnel closed from 8pm each evening, until Friday.

The cameras will be installed in both directions on the A289 between Anthony’s Way and Maritime Way and will enforce the current 50mph speed limit.

Watch: Three things you need to know about the changes to the Medway Tunnel

Once they are in place, Medway Council will be able to switch on the much-anticipated traffic lights, located on the Gillingham side of the tunnel.

The controls will briefly hold back traffic, creating a gap on the Strood side so motorists can leave the estate, which employs 6,000 people, more easily.

The lights were due to be in use from December but were delayed after a safety assessment called for cameras to stop people speeding through the tunnel when the lights go green and motorists have a clear road ahead.

Andy McGrath, assistant director of frontline services, recently said: “We hadn’t expected to have to put the cameras in, but in hindsight I can see it is the right thing to do.”

The tunnel will be closed between 8pm and 5.45am for up to four nights and the cameras will be operational upon completion. But the council has been unable to confirm when the traffic lights will be switched on and what times of the day they will operate.

The cameras are expected to be trialled later in July.

People working on the estate have been calling for traffic lights on the Anthony’s Way roundabout for many years, to allow traffic to exit more quickly, but the council rejected the idea because they did not want red lights causing a queue of traffic waiting in the tunnel.

The authority has already widened the entrance to the estate at the roundabout and realigned the exit.

It has also installed traffic-monitoring cameras so people can check a live online feed.

Roadworks to improve the A289 and the Anthony’s Way, Sans Pareil and Four Elms roundabouts will start in autumn 2017.