Mandatory Credit: Photo by Dinendra Haria/REX/Shutterstock (9111462g) An Industrial action poster at Finsbury ParUnderground Station Tube strike preparations, London, UK - 03 Oct 2017 A majority of London underground drivers belonging to the Aslef union are due to strike on Thursday 5 October 2017 in a row over demands for a four-day week. In addition RMT union members at Southern, Merseyrail, Arriva Rail North and Greater Anglia plan to strike on Tuesday 3 and Thursday 5 October.