The European Rail Traffic Management System (ERTMS) is an initiative backed by the European Union to enhance cross-border interoperability and the procurement of signalling equipment by creating a single Europe-wide standard for train control and command systems.
[5] In 2007 the British Government published its response to a European Union directive requiring the use of ERTMS on High Speed (TEN-R) and Conventional Trans-European Railway Network (TEN) routes.
[6][7] The response proposed a roll-out plan of ERTMS equipment on existing lines that would be completed by 2044, though the actual timing of the programme will depend on changing circumstances.
[8] In 2009, the Rail Safety & Standards Board confirmed that km/h would be used on ERTMS lines in the United Kingdom.
[9] With the ongoing introduction of ERTMS, it is foreseen that the metrication of British rail transport will be completed over the next few decades.