London Underground has apologised for the disruption to commuters’ travel to work on Wednesday (October 7) but that has not stopped rail unions demanding a reversal of cuts to the service.

LU’s operations director Steve White said: “I apologise for the disruption caused to Tube customers using the Circle, District, Hammersmith & City and Metropolitan lines this morning.

“The disruption was caused by signal failures at Aldgate East and Baker Street, which have now been resolved by our technical staff.

“We will be refunding customers who were affected by the disruption, and are working to restore the lines to a good service as soon as possible.”

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General secretary Mick Cash said: “This has been yet another grim 24 hours for London commuters. RMT has warned repeatedly that cuts to staffing, budgets and maintenance on both tube and rail has left services permanently on a knife edge and last night and this morning we have seen what that means in practice.

“RMT shares the anger and frustration of passengers caught up in this shambles and the union will continue to fight for a reversal of the cuts programme which threatens public safety as demand continues to surge.”

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At lunchtime there were still minor delays on the Circle, District and Hammersmith & City lines

Meanwhile the rail service generally was dogged by delays. South West Trains services to and from London Waterloo were severely disrupted after a person was hit and killed by a train at Surbiton.

Overhead wire problems between Ebbsfleet International and Stratford International caused delays of up to 30 minutes.