Passengers face disruption after a 'safety-critical electrical fault' forced the closure of the railway line between Amersham and Aylesbury Vale Parkway.

Buses are replacing trains today (Wednesday, April 8, after Network Rail identified an electrical issue affecting the signalling system, which is essential for keeping services running safely.

Engineers need full access to the track to carry out inspections and repairs, meaning the line must remain closed for the day, though efforts are under way to reopen the route on Thursday.

A shuttle service between Amersham and Aylesbury had already been operating in place of the usual timetable, but rail replacement buses are now running instead.

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Passengers travelling between London Marylebone and Aylesbury Vale Parkway via Amersham are being warned to expect significantly longer journey times.

Those who typically use the Metropolitan Line via Amersham are advised to travel on London Underground services between Amersham and Baker Street, with replacement buses connecting at Amersham.

Meanwhile, passengers travelling directly between Aylesbury and London are being told to use train services via Princes Risborough.

Adam Checkley, infrastructure director for Network Rail's Central route, said: "I am sorry for the added inconvenience this will cause but we have had no choice but to close the line while we complete a full survey to identify and fix this safety-critical issue.

"We will reopen the line as quickly as we can and I thank passengers for their understanding."

Michael Stewart, commercial and customer strategy director at Chiltern Railways, said: “I understand these short-notice works will impact our customers and I would like to thank them for their patience while they are being carried out tomorrow (Wednesday 8 April).

“A rail replacement service will be in operation instead of the planned shuttle trains between Aylesbury Vale Parkway and Amersham.

"If you are travelling in the affected area, please check your journey planners which will be updated this evening as journeys will be subject to further disruption tomorrow.”

Journey planners are being updated overnight, and passengers are being urged to check before they travel.

For the latest information, customers can visit the National Rail website.