On Wednesday, a small number of trains operating from depots in Salisbury and Exeter began to report performance problems. On Thursday, it was discovered that the problem was linked to the trains' fuel, with those trains unable to reach their normal top speeds.

The issue is now under investigation and the affected trains have been taken out of service for inspection and maintenance. As a result, there are fewer trains available to provide the usual number of services on the West of England Line, in the Romsey area, and other destinations west of Salisbury.

• One train per hour will run between Basingstoke and Salisbury and one train every two hours will run between Salisbury and Exeter St Davids
• One train every two hours will run between Southampton and Salisbury via Romsey and services to Westbury and Yeovil Pen Mill will not run
• Trains have been affected by a problem with fuel meaning fewer services can operate

Stuart Meek, SWR's Chief Operating Officer, said:

"We're very sorry for the disruption that will be felt by our customers on the West of England Line, in the Romsey area and other destinations west of Salisbury. Over the last two days some services have suffered delays due to a fuel problem and so we have had no choice but to withdraw the affected trains.

"With fewer trains available and a risk of delays, which would have a knock-on effect on the wider network, we have had to make the difficult decision to operate an amended timetable. While we appreciate it is frustrating that fewer services will be operating, this timetable does give our customers a service they can have confidence in.

"We really appreciate our customers' patience and advise them to check before travelling. We will provide an update when we know we can reinstate the usual timetable and run services as normal."