TWENTY thousand Tube workers are to ballot on strike action over the prospect of “absolute chaos” if hastily drawn-up plans to run all-night services are implemented.

Four trade unions have united in a campaign of resistance to the plans, which rail union RMT says will “rip up the safety rule book” and hit crucial engineering and maintenance work.

The other three unions are Aslef, representing train drivers, TSSA, which organises white-collar staff, and general union Unite.

RMT and Aslef members are already balloting on the proposed action, while Unite and TSSA are expected to begin shortly.

The introduction of all-night and all-weekend services has been coupled with what RMT calls an “unprecedented assault” on working conditions, pay, jobs and safety.

The union is also embroiled in disputes over station staffing and the closure of ticket offices.

RMT general secretary Mick Cash said the four unions were “united and balloting for action over the looming disaster for staff and passengers alike which is due to be ushered in under the guise of (London Mayor Boris Johnson’s) ‘night Tube’ vanity project in just 12 weeks’ time.”

He charged that the plan had been “cobbled together,” adding: “It is simply outrageous that management, in a mad dash to bulldoze through the night-running stunt, have smashed apart long-term agreements and have resorted to trying to bully staff into accepting roster changes at a local level.

“The message from RMT and our sister unions is clear — we are not having it.”