Preparatory work will start on the Airdrie to Bathgate rail link after the scheme received Royal Assent.

Network Rail now have the legal powers to deliver the link between West Lothian and North Lanarkshire.

The Airdrie-Bathgate Railway and Linked Improvements Bill now becomes an Act of Parliament after receiving unanimous support in the final debate.

Ron McAulay, Network Rail's director for Scotland, said: "Royal Assent provides us with the legal permission to proceed with construction and delivery of this immensely important addition to Scotland's railway network.

"Following the successful passage of the bill through the Scottish Parliament in March, Royal Assent is the milestone we have been working towards over the last two years.

"Network Rail will now seek to move onto site imminently to implement the first phase of the project.

"Commuters in West Lothian will be the first passengers to benefit, with improved reliability on the Edinburgh-Bathgate line as early as next year."

It is anticipated that services will be running the length of the new railway in December 2010.

Network Rail said the environmental benefits include offering a public transport alternative to travelling by car via the M8 and reducing congestion.

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Opening of new rail link delayed

BBC News: 10 May 2007

The opening of a new rail line which will see the introduction passenger services between Stirling and Alloa for the first since 1968 has been delayed.

The rail line had been due to open in the summer

The £70m Stirling-Alloa-Kincardine track, which will also take more freight off the roads, was due to open in summer 2007.

A spokesperson for the rail project said the completion date was "under review" to allow extra safety work.

The final cost of the rail line is also expected to increase.

The Scottish Executive had originally earmarked £30m for reopening the 13-mile stretch of track between Stirling, Alloa and the Longannet power station in Kincardine.

'Minimum disruption'

But the cost has more than doubled to £70m since the project was given the go-ahead.

A spokeswoman for the project said the delay in opening was the result of upgrade work to a level crossing, which was being carried out in the interest of public safety.

However, she did not reveal how much this would increase the cost.

She added: "The move from a half barrier to a full barrier level crossing with CCTV will have an impact on the completion date and on cost.

"The project team is working to keep these changes and any disruption to a minimum whilst safety continues to be of utmost importance."

The project will reopen about 21km of abandoned railway lines between Stirling and Longannet Power station.

It will also take freight off the Forth Road Bridge.

The railway line also aims to provide a more efficient freight route for coal from Ayrshire to Longannet.