Some train routes will not run through St Pancras station over Christmas while a rail bridge is replaced in Camden.

Network Rail has revealed that due to planned engineering works, some journeys through the station will be affected from December 21 until December 29.

There will be no East Midland Railway services to Bedford, or Thameslink services between St Pancras and Harpenden over this period.

Passengers who usually take the train north from the station have been advised to use different London stations and connecting buses to reach their destinations.

Among other works on the line, bridge deck on a road over the rail bridge at Agar Grove in Camden will be replaced.

It comes as Network Rail said that while 95% of the train network will run as usual over the festive period, some other routes will also be affected.

Works include replacing 45 sets of points (movable sections that transfer a train from one track to another), rebuilding four bridges, installing 40km of new signalling cables, renewing 17 level crossings and testing and switching on seven new signalling systems.

Services will not call at London Paddington between December 27 and 29 while signalling work needed for trains to run to HS2’s new Old Oak Common station takes place.

Some trains will instead be diverted via London Euston, with the majority starting or stopping at Reading and Ealing Broadway.

Work at Bishopsgate Tunnel means London Liverpool Street will be closed from Christmas Day until January 2.

Greater Anglia services, including Stansted Express, will be diverted via Stratford. London Overground services will terminate at London Fields.

Helen Hamlin, Network Rail’s director of system operations, said: “The festive period is a unique opportunity, when fewer people are travelling, to do big pieces of work to make services better, more punctual and more reliable.

“The major projects we’re undertaking would otherwise take many weekends to complete and cause much more disruption.

“Whilst roads are busier during the holidays, it’s actually one of the quietest times on the railway, meaning we can improve things whilst causing less disruption to passengers and freight flows.”