An "ongoing" cyber attack has delayed a train operator's plans to extend contactless pay-as-you-go payment across its whole network.

c2c confirmed that the planned launch of the contactless payment system across its entire route has been put on hold due to a cyber security incident affecting Transport for London (TfL).

The plan had been to begin the rollout on September 22 with a total of 47 stations outside London, including 15 stations on the c2c network, set to benefit from pay-as-you-go with contactless.

TfL's chief technology officer, Shashi Verma, said that the security measures taken to combat the cyber attack mean that it is now "not possible" to deliver the system changes.

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He said: "We are working with the Department for Transport and the Rail Delivery Group to reschedule and we apologise for the delay."

Rob Mullen, managing director at c2c, added: "The serious nature of the ongoing Transport for London cyber attack means it is not possible to launch pay-as-you-go with contactless across our route as planned on September 22.

"While this is extremely unfortunate, we recognise that it is vitally important that all issues are fully and satisfactorily resolved by TfL before we move forward."

Mr Mullen said that c2c is currently "working closely" with industry partners and TfL to agree a new launch date, which will be shared with customers in "due course".

c2c's east London stations include West Ham, Barking, Rainham and Upminster.