Rail bosses admitted services have not been up to scratch as investigations continued into a fault which caused hours of delays.

Service provider Southern Railway apologised to customers for the delays caused by the electrical fault near Clapham Junction which brought services to a standstill.

Politicians also weighed in as they called for more compensation and said “the travelling public has had enough”.

Network Rail, which maintains the country’s railways, said it was still investigating what caused the fault on Thursday which severely affected both Southern and Thameslink services on the Brighton main line.

According to rail watchdog Delay Repay Sniper commuters who managed to complete their journeys between Brighton and London Victoria and London Bridge faced 1,346 minutes of delays throughout the day.

The website also reported a spike in new users with 250 new subscriptions just for commuters on the Brighton line.

Some commuters were left stranded for hours the morning of the power failure and knock on effects were still being felt yesterday morning as engineers worked to solve residual problems.

A spokesman for Southern said: “We know that our passengers have not been getting the service they expect from us and for this we apologise.”

He added: “The last three months have seen an improvement in punctuality and although we know there is still much to do, we are moving it in the right direction.”

Caroline Lucas, Green candidate for Brighton Pavilion, said: “The rail travelling public has had enough. “The bottom line is we’re not getting the service we pay for and that has to change – people absolutely rely on these services.

“Yesterday’s rail farce was completely unacceptable – and typical of a system that is under-resourced, over-stretched and fragmented.”

Norman Baker, Liberal Democrat candidate for Lewes, called on the train company and Network Rail to offer 10% off rail fares for a month to compensate passengers for their “appalling poor performance this year”.

Southern said there were “no plans to offer additional compensation over and above our Delay Repay compensation scheme.

“However, we have recently added an enhancement to the scheme.

“Details are available at southernrailway.com/delayrepay.”

A spokesman for Southern said: “We know that our passengers have not been getting the service they expect from us and for this we apologise. We operate on one of the most congested networks in the country and this fact alone contributes to heightening the effects of even the smallest delay which impacts on performance.

“It is clear that in recent years, as demand has grown (the number of passengers on Southern has grown by 32% over the past five years), performance has declined.”