To ask Her Majesty's Government what responsibility, if any, they have for ensuring that comprehensive road maps of cities are available including details of no right turns.
Local authorities are responsible for managing their road networks, including implementing measures such as right turn bans. It is for them to ensure these and other traffic restrictions are properly signed on-street so that drivers are aware of them. Drivers are responsible for ensuring they follow the rules of the road and are not in breach of any restrictions.
The Department for Transport has no responsibility for producing road mapping. Commercial mapping companies are responsible for ensuring the maps they produce are accurate.