London Underground train drivers will strike on Christmas Eve after talks to avert a 24-hour walkout collapsed.
Hundreds of thousands of passengers face chaos on the Piccadilly Line after negotiations between union leaders and LU management ended in deadlock.
Steve Grant, London district secretary fordrivers' union Aslef, told the London Evening Standard: "There are no new talks planned. As far as we are concerned Friday's strike is on."
Signal workers action
In a separate dispute, signal workers on all lines were today poised to vote for a New Year's Eve strike.
The dispute is about a driver who was demoted when he was found to have passed four separate red signals.
Aslef said he is being treated more harshly than others who have committed the same offence.
They want him reinstated immediately and amitted to a retraining programme.
In a third LU dispute, District Line drivers are threatening to turn up late for work in the new year.