There will be more disruption on the trains in East Anglia tomorrow as heat-related speed restrictions are put in place.

The region's train operator, Greater Anglia, said services will be operating at reduced speeds as Network Rail has imposed heat-related speed restrictions on the Greater Anglia network from 12pm until 9pm.

The speed restrictions have been put in place to protect the railway infrastructure and keep services running as temperatures continue to rise.

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The restrictions were necessary to prevent rails from buckling in the heat, and to protect overhead lines, which may sag when they get hot.

The full, scheduled Norwich to London Liverpool Street service will run but there may be delays of 40 minutes or more to journeys and some services may be cancelled or altered at short notice.

But Great Anglia has already cancelled more than 30 services including a number between Ipswich and London Liverpool Street.

MORE: Heatwave alert to remain in place for Norfolk and Waveney but temperatures will drop by end of week

A spokesperson said, 'We are very sorry for any inconvenience caused by these heat-related speed restrictions and the amended timetable that we have to run as a result of the slower speeds.'

Advance purchase ticket holders can travel on earlier or later trains if their booked service is cancelled.