Avanti West Coast has cut its timetables and suspended ticket sales due to "unofficial strike action" by drivers.
The train operator said it will run as few as four trains per hour from Sunday in an attempt to halt the short-notice cancellations which have plagued its operations in recent weeks. It normally operates up to seven per hour on the West Coast Main Line.
Services between London Euston and Manchester appear to be the worst affected by the cut, with train frequencies reduced from three per hour to just one.
