Giant, cursive graffiti stating: “The illusion of democracy” has been sprayed on the walls of a posh development overlooking the westbound platform at Dalston Kingsland Overground station.

It is not known how vandals carried out their work on the side of Fifty Seven East, where one-bed flats go for north of £595,000, but transport chiefs have spoken of their zero-tolerance of such efforts.

A TfL spokesperson said: "Our teams work hard to ensure our trains and stations remain a pleasant environment for our passengers. We have a zero tolerance approach towards vandalism on the network and refer all instances of offensive vandalism to the police for investigation."

Taylor Wimpey, developer of Fifty Seven East, did not want to comment.