A faulty radio system is disrupting train services across southern England - here are the seven train companies affected
National Rail says the system is how train drivers and signallers communicate
It also warns passengers to expect "major disruption", including cancellations and delays, "until the end of the day"
South Western Railway tells its customers "we do not have an ETA yet for when signalling will be back to normal", while Thameslink warns of delays to Brighton, Horsham and Three Bridges
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Network Rail has just apologised to passengers for disruption to rail services in the south-west and south of England.
"Staff have worked to resolve the fault, and train services are now returning to normal," a spokesperson says.
Malcolm Senior
Reporting from Barnes station
Blue skies but delays and cancellations at Barnes station
I had been hoping to have a day out in the Sussex countryside - but my train ground to a halt after one stop.
It soon became apparent there was a major problem, and I decided to divert my day out.
One of the guards on the train tells me things are getting back to normal.
So far, I can see services are running about 60-80 minutes late, so no trip to Sussex.
"The fault with the radio system between the driver and the signaller that is affecting services on the South England network has now been resolved", National Rail says in an update.
It warns that "some services may still be delayed by up to 90 minutes or cancelled whilst service recovers".
Major disruption is expected until the end of the day, it adds.
Southeastern has confirmed that its services are not affected.
It says in an update on X: "We would like to confirm that the ongoing fault with the radio system between the drivers and the signallers affecting the South of England are NOT affecting our services".
"There are no ongoing disruptions to our services," it adds.
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Southern Rail also says services to and from London Victoria are particularly affected, as well as its West Coastway route between Brighton and Portsmouth/Southampton.
Check Southern Rail's website, external for the latest updates.
Thameslink warns of likely delays on its services running to and from Brighton, Horsham, and Three Bridges.
"Please carefully check station information screens and listen to announcements before you board," the company says.
There's a warning from South Western Railway now, which says services across its entire network "may be cancelled, delayed by up to 90 minutes or revised".
It goes on: "Our operations and engineering teams are working with signallers to find and fix the fault. We do not have an ETA yet for when signalling will be back to normal."
The operator advised passengers to consider using buses “while the fault is being investigated".
Gatwick Express is warning of delays for services running to and from London Victoria, adding "further disruption is likely", including cancellations.
Passengers who are currently travelling should listen to announcements and check station screens for the latest information.
Tickets can be used on alternative routes at no extra cost, the train company says.
National Rail says the disruption is caused by "a fault with the radio system between the driver and the signaller".
"Some services may be delayed by up to 90 minutes or cancelled as a result," it says.
"Major disruption is expected until the end of the day."
National Rail has published this list of train companies affected by the delays:
A radio system is disrupting train services across southern England.
Passengers are being warned of major disruption, with delays and cancellations expected until the end of the day.
We'll bring you more in the next few moments.
