There are severe delays at the Dartford Tunnel and on the M25 owing to a “large liquid leak” which has caused “extensive damage”.

Two lanes are shut on the major motorway anticlockwise between Dartford and Lakeside after the spillage from a maintenance vehicle during overnight works.

There is standstill traffic stretch back past the Swanley Interchange, towards junction 4 for Orpington, as well as long queues on the A2 back towards the M2 at Strood.

A National Highways spokesperson said: “The A282 northbound Dartford East Tunnel is closed following overnight roadworks which are going to overrun their pre-agreed end time due to a maintenance vehicle breakdown within the tunnel which requires emergency resurfacing works before the tunnel can re-open.”

In a later update the government-owned company confirmed a large volume of hydraulic liquid had leaked during the essential works.

This has led to the continued closure of the east Tunnel, as around 400 metres of the road require resurfacing.

It also means capacity for traffic headed through the tunnel, towards Essex, has been halved.

The taller right-hand tunnel needs resurfacing and is expected to stay closed for most of the day.

Traffic is advised to follow the M25 clockwise as an alternative route, through the left-hand tunnel.

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The M25 is also shut clockwise between Junction 5 for Sevenoaks and Junction 6 for Godstone due to a serious lorry fire.

The blaze broke out last night and has also closed the M26 London bound from Junction 2A for Wrotham to Junction 1 for the M25.

The network operations manager for National Highways in the South East, Robert Bell, has advised drivers to avoid the area if they can.

He added: “The challenging nature and extensive damage these incidents have caused means the closures are going to run into tonight’s commute and my advice is to please plan your journey, allow extra time, and avoid the area if you possibly can.

“We have diversions in place but due to these incidents impacting each other there is already significant disruption in the surrounding areas and we expect this to get worse as we move towards the evening commute.

“Getting these roads open is our absolute priority and we are doing everything we can to make that happen.

“The M25 and the Dartford crossing are major parts of the strategic road network, and we understand the inconvenience and disruption any closure has.

“We appreciate people’s patience and understanding while these significant repairs are undertaken.”

Further along the M25 is closed clockwise following a fire involving a Tesco lorry between junction 5 for Sevenoaks and junction 6 for Godstone.

The blaze broke out last night (Sunday) and has also closed the M26 London bound from junction 2A for Wrotham to junction 1 for the M25.