First Great Western is asking passengers to check journey times before they travel over the Christmas period as Network Rail carry out vital works to progress the Crossrail, electrification and Reading projects, which will impact train services to and from Devon and Cornwall.

A number of our train services will operate without change over the Christmas period, but while work is underway to "minimise disruption to journeys" services will be affected on certain dates.

Alterations are as follows:

Earlier than usual Christmas Eve closedown, with service reductions starting from 5pm for high speed, long distance services. Last trains leaving London Paddington by 9.30pm.

Two service plans for 27 December 2014 •

Before 1100: A limited number of high speed trains from London Paddington will serve Devon and Cornwall, South Wales, and stations to Bristol .

High speed, intercity, services towards London will terminate at Reading and passengers are advised to use South West Trains services between Reading and London Waterloo before 1045.

The company will continue to operate a service an hour to Devon and Cornwall.

Some services will be diverted, increasing journey times from London Paddington by up to 40 minutes. Please check departure times

First Great Western MD, Mark Hopwood said: “We have been talking to our passengers about these projects for some time and we are grateful to them for their understanding while we work to keep disruption to a minimum.

“The upgrades are vitally important to improve our customer’s travel experiences both now and for the future, paving the way for faster and more reliable services.

“A significant step towards that will see the Reading Flyover opened in the New Year, which will remove a bottleneck at one of the busiest locations on our network and reduce delays.”

The £45m Reading viaduct is one of the final phases of the Reading Redevelopment project which will separate fast moving trains between London and the West from slower moving freight trains travelling between the South Coast and the Midlands.

The new Reading viaduct is due to be in use from Sunday 4 January.

The entire redevelopment project will be completed in summer 2015. This will follow the final installation of track, after the railway to the west of the station is re-modelled over Easter 2015.

Patrick Hallgate, Network Rail’s managing director for the Western route, said: “This work represents a major investment in this part of the rail network and will lead to huge improvements for passengers, including more services and reduced journey times, enhancing their travelling experience.

“We have been working closely with First Great Western to minimise disruption and ensure the work is completed in as short a timeframe as possible. This is an exciting time for the Great Western route and we ask that you bear with us over the Christmas period as we undertake this extensive improvement work to create a better railway for passengers and those living near to the railway line.”

Passengers should plan their journeys before travelling on the affected dates, by visiting www.journeycheck.com/firstgreatwesternor calling First Great Western’s customer services team on 03457 000 125 for more information.