British rail unions on Friday announced they would join a series of already-planned strikes in October over pay and conditions.
Members of the Transport Salaried Staffs' Association (TSSA) and Unite will take part in industrial action in early October.
"To be faced with a three year pay freeze during the worst cost of living crisis in decades is disgraceful,” Unite's general secretary Sharon Graham said in a statement.
The announcement from TSSA came after the union cancelled strike dates scheduled for September following the death of Queen Elizabeth.
"We would much rather find a fair negotiated solution to this now long-running dispute, but we simply have no choice," TSSA general secretary, Manuel Cortes said. (Reporting by Farouq Suleiman; editing by William James)