RMT members who are cleaners on the rail network will take industrial action over "serious bullying, claims of discrimination and poverty working conditions" on the GWR train cleaning contract operated by Servest UK.
Members have been instructed not to book on for any shifts between 05:59 on Friday 23 December and 05:58 on Saturday 24 December, and cleaners will be picketing at Paddington Station from 06:00 tomorrow.
RMT accused GWR of "hiding behind its sub-contractor to avoid proper responsibilities to the workers who clean their trains".
The union is calling for current agency workers to be made members of GWR staff "to end the current situation of a two-tier workforce", and said GWR "refuses to commit to meaningful talks on making adjustments to their contract with Servest UK".
RMT general secretary Mick Cash said: “RMT’s cleaner members on GWR will not stand by while they are mercilessly exploited by privateers, while rail companies fill their coffers as fares soar through the roof. That is why they are taking strike action tomorrow."
“GWR and Servest UK can bring an immediate resolution to this dispute by immediately addressing the issues over pay and other grievances and starting the process of bringing these workers back in house so that they are on the same terms and conditions as the rest of the staff. The union remains available for talks.”
A GWR spokesman said: “We are aware that contract staff at Servest, which carries out cleaning on board our trains, are planning to take industrial action tomorrow. We do not expect this to affect rail services, and strongly encourage both parties to continue to resolve their dispute.”
Earlier this week, RMT said it was open to the idea of a Christmas truce and could suspend strike action over the festive period – but added that it was up to the government to make peace.