Greater London is often referred to as "the City" or "the Square Mile" and it forms the main financial district. Archaically, the urbanised area of London was known as the Metropolis. In common usage, the terms "London" and "Greater London" are usually used interchangeably. Greater London is officially divided for some purposes, with varying definitions, into Inner London and Outer London. For some strategic planning purposes it is divided into five sub-regions. Greater London is under the strategic local governance of the Greater London Authority (GLA). It consists of an elected assembly, the London Assembly, and an executive head, the Mayor of
Central London and Southwark, parts of St Pancras, St Marylebone, Paddington and a small part of Kensington. The area had an estimated population of 400,000 and occupied . During the passage of the London Government Bill an amendment was put forward to create a central borough corresponding to the definition used at the 1961 census. It consisted of the City of London, all of Westminster, Holborn and Finsbury; and the inner parts of Shoreditch, Stepney, Bermondsey, Southwark, Lambeth, Chelsea, Kensington, Paddington, St Marylebone and St Pancras. The population was estimated to be 270,000. Central London Central London (also known less commonly as