A points failure at Moorgate means trains are unable to run between Finsbury Park and Moorgate.
Engineering work is taking place between London Liverpool Street and Enfield Town / Cheshunt / Chingford, closing lines until 10:15.
Replacement buses will run between:
Engineering work is taking place between Hither Green and Sidcup / Chislehurst closing all lines.
Buses will replace trains between Lewisham and Sidcup / Orpington.
Engineering work is taking place between Cholsey and Didcot Parkway, as well as between Maidenhead and Tilehurst, closing some lines.
As a result, no trains will call at Didcot Parkway.
Replacement buses will run:
Twice hourly between:
Engineering work is taking place around Warrington Central, closing all lines.
No trains will run on Tuesday 25 and Wednesday 26 December.
East Midlands Trains:
Engineering work is taking place between Swanley and Rochester on Saturday, and between Bromley South and Rochester / Borough Green & Wrotham on Sunday, closing all lines.
Saturday:
Engineering work is taking place between Vauxhall and Clapham Junction, closing some lines.
As a result of less lines being available, a reduced service will operate between London Waterloo and Surbiton / Woking / Dorking.
Engineering work will be taking place between Whitton and Virginia Water, and between Ascot and Windsor & Eton Riverside, closing various lines.
Saturday
Engineering work is taking place between Bedford and Leicester overnight from Monday evening until Saturday morning.
As a result, the following trains will be amended:
Monday to Thursday:
An obstruction is on the track between Walmer and Deal, causing disruption to journeys between Dover Priory and Ramsgate. Train services running through these stations may be delayed or revised.
Disruption is expected until 11:30.