Greater London is made up of 32 London Boroughs and the City of London that provide the vast majority of municipal services. Each has a mayor or Lord Mayor. The powers and responsibilities of London Boroughs, and the local authority responsibilities of the City of London Corporation are set out in statute law, not delegated by the Mayor of London.
The Mayor of London is responsible for public transport, Fire and Rescue Services, major highways, some major town planning issues across the 32 London Boroughs and the City of London, and policing across the 32 London Boroughs. The Mayor of London has no general authority over any of the 33.