Delays of up to 30 minutes on East Coast between Kings Cross and Doncaster due to signalling problem at Peterborough.
Mainly affecting northbound services.
Trains are running at reduced speed through the affected area, resulting in delays.
There is no estimate for a normal service.
More top news
Kerrie Gosney brings you Sunday night's forecast
Cold with wintry showers overnight and on Monday.
Cold air from Canada will turn showers wintry overnight into Monday morning. Snow could settle over higher routes. Icy patches possible