Tube workers are threatening a "complete closedown" of the London Underground network over the bank holiday weekend amid a dispute over working conditions.
The Unite trade union said 40 technicians in the London Underground power control room are planning to walk out from one minute past midnight on Saturday until Tuesday morning.
The technicians, based in TfL's power control room, are key to providing power to 270 stations in the network.
Conciliation service Acas was today overseeing talks between Unite and London Underground to try to avert the planned walkout.
Unite regional officer Hugh Roberts said: “There is a real possibility that the underground could close down over the bank holiday weekend.
"Unite is working very hard to achieve a fair settlement for our members – and to avoid the industrial action. The ball is very much in the management’s court."
The union acknowledged that the dispute is "complex", and relates to a transfer of undertakings from London Underground to other organisations, and then back again.
Mr Roberts added: "The issue here is broken promises, unfair treatment over differentials and worsening conditions.
"London Underground management’s penny pinching attitude is not being driven by common sense, but by the background agenda of budget cuts in the Treasury’s funding."
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Richard Jones, London Underground's head of command and control, said he was "happy to discuss" grievances raised by staff.
But he added: "We are disappointed that the unions have chosen to call strike action and we would urge all unions involved in this dispute to continue discussions to resolve this matter without the threat of industrial action.”
