A DAMAGED signalling cable near Havant has seen all train lines blocked.
The signalling problems are affecting all services and are expected to last all of today.
Network Rail have been working through the night but engineers have been unable to fix the issue.
A statement on South Western Railway website said: ‘We’re sorry for disruption yesterday and today, caused by a damaged signalling cable near Rowlands Castle.
‘A number of issues have occurred overnight, and trains are not able to run between Bedhampton and Rowlands Castle.
‘Trains may take the longer alternative route via Eastleigh at short notice.
‘We’re working to arrange for replacement buses to run on affected routes but the wide area affected means that this may take some time.’
Some trains, including Southern Railway and Great Western Railway services, will be changed or cancelled.
Tickets will be available to use on bus routes.
A Network Rail spokesman said: ‘Owing to a signal fault, services between Portsmouth and Chichester are likely to be affected during the morning peak.
‘This is also likely to impact other services in the Portsmouth area and passengers are advised to check before they travel.
‘We are doing all we can to fix the fault and apologise for any inconvenience caused.’
For more information or to check timetables visit southwesternrailway.com.