Great Western Railway reported severe disruption after a points failure between Oxford and Didcot Parkway blocked every line on the route to London, leaving trains unable to move this morning.
The fault concerns technical equipment associated with the railway tracks.
GWR said services passing through the affected stations faced cancellations or delays, with disruption expected to continue until 10.30am.
A number of trains bound for London Paddington were cancelled as a result.
An update issued by GWR on November 8, 2026, confirmed that all lines were blocked because of the points failure between Oxford and Didcot Parkway.
The company advised passengers to check their planned journeys before departure.
Trains serving London Marylebone continued to operate, although passengers were told to verify their arrangements before travelling.