A seven mile stretch of the M25 is set to shut down in both directions this weekend.
Motorists have been advised to avoid the area between junctions 9 and 10 in Surrey – from 9pm on Friday to 6am on Monday morning.
Instead, drivers have been urged to stick to the planned 19-mile diversion route, which will send vehicles through parts of Surrey and Greater London.
The closure is the second of five planned on the motorway after junctions 10 and 11 were temporarily shut down in March.
Although there were fears the closures in March would lead to widespread congestion, it was later reported traffic through the diverted areas was down around two-thirds after a widely shared awareness campaign.
Those travelling to or from Heathrow and Gatwick airports are set to be the worst affected, with the National Highways warning motorists it expects long delays.
Meanwhile, drivers will also be subjected to London’s ultra low emission zone (ULEZ) rules if they move off official diversion routes during this weekend’s M25 closure.
National Highways senior project manager Jonathan Wade told the PA news agency: ‘Although the (ULEZ) cameras will be active, no enforcement action will be taken.
‘However, if you ignore the diversion signs and do your own thing, then if your vehicle’s not compliant you do run the risk of getting caught.
‘You’ll be perfectly safe as long as you follow the diversion routes.’
RAC spokesperson Alice Simpson also warned drivers not to rely on their sat navs during the closure.
‘Planning ahead is absolutely vital,’ she said.
‘Rather than relying on a sat nav, check the planned diversion routes ahead of time and be prepared for long delays.
‘It’s also a really good idea to check your vehicle’s oil and coolant levels, tyre pressure and tread depth all before setting off to reduce the chances of a very unwelcome breakdown.’
Vehicles diverting from the planned diversion routes which do not comply with ULEZ standards will have to pay the £12.50 daily fee if their vehicle does not meet minimum emissions standards.
Failure to pay the charge when required can result in a £180 fine, reduced to £90 if paid within 14 days.
Get in touch with our news team by emailing us at webnews@metro.co.uk.
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