Union leaders have claimed that a strike by thousands of London Underground workers caused "severe disruption" to Tube services, with further problems forecast for Monday morning's rush hour.
Members of the Rail, Maritime and Transport Union and the Transport Salaried Staffs' Association walked out at 6.30pm for 24 hours as part of a long-running dispute over 800 ticket office job cuts. It was the fourth stoppage in recent months following the collapse last week of talks aimed at breaking the deadlock.
Transport for London (TfL) pledged to run as many Tube services as possible, although it warned there will be disruption throughout the whole of Monday with services not returning to normal until Tuesday.
The RMT said there was severe disruption on the Jubilee Line due to signal failure at Westminster and station closures due to the immediate impact of the strike
"The District, Hammersmith and City and Victoria Lines are already severely disrupted due to the immediate impact of strike action. The impact of the action has kicked in earlier than on previous strikes as RMT and TSSA members remain rock solid," said an RMT spokesman.
But a Transport for London spokesperson said: "The claim that the strike is already causing significant disruption is simply untrue. The Jubilee line experienced delays for a short period of the evening due to a signal failure at Westminster, which was totally unrelated to the unnecessary strike action called by the leaderships of the TSSA and RMT unions. 100% of our usual train service is in operation, and only a few stations have closed early."
Mike Brown, London Underground's managing director, accused the unions of being "cynical" and pledged to do everything possible to keep London moving during the latest strike.
Writing on his blog, which went live on LU's intranet, he said the behaviour of the unions this week and during the current dispute "brings into question the motivation of some of those who claim their role is to protect their members."
"I hope you will think again about losing another day's pay and will consider coming to work on Sunday and Monday to help run a service."
RMT general secretary Bob Crow said: "It is incredible that LU management would not agree to a 12-week suspension of the cuts to allow a thorough safety evaluation on the impact on each station of their cuts plans. That shows complete and utter contempt for the safety of both their passengers and their staff. With more chaos as a result of infrastructure failures this morning, adding to a month of misery, Londoners can see the real impact of the LU/TfL cuts plans for themselves and it is those very same safety-critical cuts that are at the heart of this dispute."