There are delays of up to 40 minutes on trains running from Oxfordshire into London Marylebone.
Chiltern Railways says this is due to problems with line side equipment between Beaconsfield and High Wycombe.
Services from Aylesbury in Buckinghamshire are also affected.
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Amanda Houston has the lunchtime forecast for the west of the ITV Meridian Meridian region.
Amanda Houston has the lunchtime forecast for the east of the region.
The latest weather forecast for the west of the region from Amanda Houston.