North-east London area

The London boroughs of Barking, Havering, Newham, Redbridge and Waltham Forest.

South-east London area

The London boroughs of Bexley, Bromley and Croydon.

South-west London area

The London boroughs of Kingston upon Thames, Merton, Richmond upon Thames and Sutton.

Middlesex area

The London boroughs of Barnet, Brent, Ealing, Enfield, Haringey, Harrow, Hillingdon and Hounslow.