Tube workers have voted to strike in a row over the transfer of staff.
The strike is expected to cause massive disruption to the capital's Tube network with commuters forced to endure severe delays.
Members of the Rail Maritime and Transport union (RMT) voted for industrial action by 750 to 60 - a 92 per cent majority.
The RMT is protesting at plans to transfer staff to the owners of Metronet, the group which maintain two-thirds of the Tube network.
The union's execution is expected to decide later today what form the strike action will take.
The RMT's general secretary, Bob Crow, said: "Our members have demonstrated their anger at Metronet reneging on an agreement they made only a year or so ago.
"This dispute is about honouring agreements and defending our members' pay, conditions and organisation, but it is also about resisting dangerous fragmentation that our members already have too much bitter experience of."
Metronet has said any strike action would be unfair as discussions with the union were still continuing.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article