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Guidance on advertisements alongside motorways and trunk roads, including guidance on advertisements on vehicles parked in fields, verges or in lay-bys is provided in paragraphs 147-148 of CLG Circular 03/2007, “Town and Country Planning (Control of Advertisements) (England) Regulations 2007”.
Outdoor advertisements are controlled by these regulations. Generally, mobile advertising billboards will require the express consent of the local planning authority before they can be displayed. It will be for the relevant local planning authority to determine whether a particular advertisement should be permitted and the most appropriate course of action to take when an advertisement is displayed in contravention of the regulations.