Disruption due on M25 and M1 to transport power station equipment

The 350-tonne equipment will take 12 hours to travel 79 miles

Overnight traffic on the M25 and M1 is due to face delays this weekend when a 50m-long (164ft) piece of equipment is moved to a power station.

The 350-tonne kit will be taken from the Port of Tilbury in Essex to Millbrook power station in Bedfordshire from Saturday evening into Sunday.

Organisers said the 79-mile (127km) journey would be the first of three, with two more happening in March.

Traffic will be held at stages of the 12-hour trip that ends about 06:15 GMT.

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"This is an essential piece of equipment for the power station which, when completed, will operate as a peaking plant and only generate electricity at times when the country's need is greatest," a spokesman for the Millbrook power station said.

He said on completion it would have the capacity to generate enough electricity for 150,000 homes.

The equipment will be accompanied by a police escort.

It will leave the Port of Tilbury at 17:45 on Saturday and take the A13 until it meets the M25, where it will continue until junction 21 with the M1.

It will then head north on the M1, leaving the motorway at junction 13, before taking the A421 towards the power site.

What closures are planned?

• The section of the M25 between Junction 21a and Junction 19 will be closed in both directions between 22:00 and 06:00 GMT

• The exit slips from the M1 on to the M25 at Junction 6a will be closed in both directions between 22:00 and 06:00

• The entry slip from the A12 on to the M25 anti-clockwise at Junction 28 will be closed between 20:00 and 05:00

• There will be a temporary holding delay of about 30 minutes at the Gallows Corner roundabout on the A12, and this is likely to be at about 22:00