The M25 is set to close near Watford this weekend so that 350 tonne power station equipment can be moved.

The motorway will be shut between Junction 21a and Junction 19 in both directions from 10pm on Saturday evening (February 24) until 6am the next morning.

The M1 and A12 slips onto the M25 will also be closed, in both directions at Junction 6a and 28 respectively.

Closures for the same stretch and during the same time frame on March 9/10 and March 23/24 are also expected to be in place during the following weeks, subjected to conditions such as weather.

There are no other roads closed around the Hertfordshire M25 and a diversion will run through local roads.

The first load, to be taken this weekend, weighs more than 350 tonnes and is more than 50 metres long. It will be escorted by police on a 79-mile journey from the Port of Tilbury in Essex to Millbrook Power Station in Bedfordshire.

It is apparently an “essential piece of equipment” for the in-development power station and will take 12-hours to get there, travelling at a walking pace when not on a motorway.

On completion Millbrook Power will have the capacity to generate enough power to provide instant electricity to power 150,000 households.