HUNDREDS of extra staff have been deployed at key railway stations in central Scotland amid expectations of major disruption to journeys as major works get underway.

Just 48 hours into work on the main Edinburgh to Glasgow railway line and the first day of its impact on commuters, around 200 additional customer service staff have been mobilised.

The Scotrail workers will advise passengers on the best travel option during vital electrification works.

More than 40 dedicated replacement buses are also on hand to shuttle between Linlithgow and Haymarket, with more on stand-by if required.

Passengers expected to face at least six weeks of significant disruption, with the Winchburgh tunnel near Linlithgow in West Lothian now closed since Saturday to allow upgrades to be carried out.

The new organisation set up by ScotRail franchise holder Abellio and Network Rail said work was "progressing well".

It also said direct travel between Glasgow and Edinburgh was still available via the Airdrie-Bathgate line to Queen Street and the Shotts line to Central.

The work is part of a £750m project to enable faster, bigger and greener electric trains to run on the line.

ScotRail has a dedicated website to advise on the disruption.

A ScotRail spokesman said: "We have hundreds of engineers working around-the-clock to complete the vital, unavoidable work in Winchburgh Tunnel as quickly as possible.

"Work commenced over the weekend and is progressing well.

"We also have over 200 extra customer service staff working at key stations to help our passengers choose the best travel option for them during these vital electrification works.

"We understand the short-term inconvenience this project will cause to our customers, however, in the longer-term this work will mean faster journeys, more seats and greener services between Glasgow and Edinburgh."

Work on the Winchburgh tunnel will mainly hit travel between Glasgow, or Stirling/Dunblane, and Edinburgh but it will also have a knock-on effect in areas such as the Fife Circle.

Many passengers will have longer journeys or bus replacements. ScotRail advised passengers to add at least 30 minutes to their planned journey times.

Meanwhile, rail services across the country faced significant additional disruption throughout yesterday after a train derailed at one of the network's busiest junctions.

No-one was injured in the derailment of the engineering train in the earlier today at the Greenhill Upper Junction, around three miles west of Falkirk.

The junction is where the main Glasgow to Edinburgh line meets with that heading towards Stirling and Alloa.

A ScotRail Alliance spokesman said: "In the early hours of Sunday morning an engineering train derailed at low speed at Greenhill Upper Junction, north of Glasgow.

"The derailment was a minor incident with only one set of wheels off the rails. The train remained upright and undamaged and there have been no injuries to staff."

The spokesman added that engineers had been on-site round the clock working to rerail the wagon and remove the train from the area, but he said the incident had caused some damage to the track below which would also require repairs.

Work on the rail improvement scheme also comes at the same time as major upgrades to the road network in Central Scotland.

Work on the £500million M8 M73 M74 Motorway Improvements Project in Lanarkshire is already leading to disruption as traffic restrictions are in force.