The Dart Charge automatic payment system will not be in place this weekend.

Drivers holding the Dartford Crossing accounts are being reminded if they use the tunnel or QEII Bridge over the next three days they will not be able to pay their toll manually until Sunday afternoon.

A National Highways spokesman said: “The automatic payment system for journeys will be unavailable because of improvements being made to the system.

“Starting from 00.01am on Friday, July 28, until late on Sunday, July 30, users will not be able to pay for crossings or access their Dart Charge accounts.

“The whole system is down so payments cannot be made via the call centre either. However, our call centre will remain open to field any queries and offer assurance to customers. Everything should be back up and running on Sunday afternoon.

”When the system comes back up Sunday afternoon, customers will be able to pay manually if they need to. We have given account holders until Tuesday, August 1, to sort out payments.”

Following the system update pay as you go customers will need to log in and enter their CVV to update their card details.

“National Highways apologises for any inconvenience caused during this maintenance period and deeply appreciates road users understanding as improvements are undertaken.”

Due to the introduction of new banking requirements, it will also be essential for account holders, including Pay as You Go customers, to re-validate their payment cards following the weekend.

Neglecting to act may result in crossings not being automatically paid due to invalid card payment details, potentially leading to a Penalty Charge Notice (PCN).

National Highways has dispatched direct communications and instructions, to those affected.

Its spokesman continued: “Previous communication stated this would be required on Friday, July 28, but due to an extended maintenance window this will now not be possible until the service is re-opened on Sunday, July 30.”

As part of the improvements, a new Service Provider (Conduent) will become responsible for vehicle identification, payment processing and account management.

Emovis, the current enforcement contractor, will continue to issue and handle enquiries for PCNs.

Anyone wanting to know more about the scheme, or for any help, can visit the Dartford Crossing charge website.