There was little sign of feared disruption this morning on the London Underground as Tube power workers began an eight day strike in a row over pensions and working conditions.
As of 8am this morning all lines were running a good service, with the exception of the district line which was running with minor delays.
However, unions maintained that London Underground's plans to run a full service were "provocative and dangerous".
Members of the Rail, Maritime and Transport union and Unite walked out at 8pm last night, warning of travel disruption in the capital.
London Underground had promised, however, that the strike action would have no impact on Tube services as it has "detailed plans" in place.
Mick Cash, RMT acting general secretary, said: "This dispute is over an all-out attack on the power control grade that would hit pensions, length of service and working conditions and damage the futures of this key group of tube workers. Management's claim that they can run the system without them is both provocative and dangerous.
"These staff are effectively the national grid for London Underground and this action will have the most severe consequences for Tube operations but has been forced on us by management wrecking the earlier talks. "
A Unite spokesman said: "The blame for any disruption will lie with the management because this dispute should have been resolved weeks ago.
"The travelling public faces the very real prospect of their journeys being disrupted because of the irresponsibility of the management."
Richard Jones, London Underground's Head of Command and Control, said: "Due to detailed planning there will be no visible impact on the network.
"We remain committed to discussions with Unite, TSSA and RMT representatives around working terms and conditions for staff in our power control team, I urge them to continue with constructive discussions rather than threaten pointless industrial action."
Unite has urged the Office of Rail Regulation to question London Underground on safety issues.
The union, which represents most of the 40 power technicians involved in the dispute, has written to ORR to challenge LUL management that its contingency plans are robust enough.
Unite regional officer Hugh Roberts said: "Serious matters of public safety arise from the way LU intends to manage the control of power during our members' strike action.
"The duration of industrial action is for several days and nights and LUL intends for two managers supervising the volunteers - to work several shifts each without a rest day. "