First Great Western is encouraging passengers from Cornwall and Devon to check before they travel this Easter as Network Rail carries out the penultimate phase of the £895m redevelopment of Reading Station.

The work to tracks will make the most of the new flyover, opened in January, and remove the need to queue to access available station platforms.

Crossrail work in the Thames Valley and electrification re-signalling around Slough will also impact journeys – part of the £7.5 billion investment in "Building a Greater West".

From Good Friday to Easter Monday (3 to 6 April) and on Sunday 12 April, Devon and Cornwall services will be diverted via Basingstoke into London Waterloo, adding up to 60 minutes to journey times.

The Night Riviera Sleeper departs from London Paddington at 2233 on the night of Thursday, April 2.

On Friday, April 3, Sunday, April 5 and Monday, April 6 the sleeper service will not operate. Instead there will be an overnight high speed train service from London Waterloo to Penzance.

First Great Western managing director 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 new viaduct is already reducing the need to queue outside of Reading Station, and this work will further improve access, improving customers’ experiences both now and in the future.”

All of these major improvement works form part of the wider £7.5 billion scheme to improve capacity and connectivity on the Great Western Main Line so that customers experience more comfortable and efficient journeys.

Network Rail’s route managing director, Patrick Hallgate, said: “This is the largest package of improvement work that we have carried out on the Western route, which once complete will improve passengers’ travelling experience by providing a more reliable service and reducing journey times.

“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 Easter period as we undertake this extensive improvement work to create a better railway for passengers.”