A fault with the signalling system between Darlington and Northallerton blocked the railway earlier.
Lines have now reopened.
While service recovers, trains running between Newcastle and York may still be cancelled, delayed by up to 90 minutes or revised.
The disruption affects LNER. CrossCountry, Grand Central and TPE services.
The stations affected are York, Thirsk, Northallerton, Durham, Chester-Le-Street and Darlington.
