A TOTAL of £12million is to be spent on electrifying the five-mile railway line between Glasgow Central Station and Paisley Canal.

Network Rail and ScotRail will jointly fund the upgrade, which will lead to thousands of commuters travelling on new air-conditioned trains by Christmas.

The alliance – the first time the two companies have teamed up in this way – is expected to trigger a number of joint projects.

The first will be electrifying what is a busy route between Glasgow and Paisley. Work is due to begin before the end of the month and will be completed before the end of the year.

It means diesel trains will be replaced by eco-friendly locos. ScotRail plans to introduce Class 314s as well as its newest fleet – the air-conditioned Class 380s.

The original cost was £28m, but that has been cut by more than half after ScotRail agreed to waive its right to compensation payments for service disruptions.

A raft of other measures have triggered significant savings, such as the decision to shorten new platforms to accommodate four carriages rather than six which will enable ScotRail to "mix and match" its rolling stock.

Susan Anderson, of Network Rail, said: "This is the first tangible benefit for rail customers to be delivered through this alliance with ScotRail."

ScotRail's managing director Steve Montgomery added: "This work is set to deliver substantial benefits for customers while driving down costs. The alliance is a leaner, more efficient way of working and sets the standard for future rail projects in Scotland."

Scotland's Transport Minister Keith Brown said: "The big winners from the investment are passengers, who will notice a marked improvement in performance, comfort and seat availability."

Today's news comes after the Evening Times revealed details on Wednesday of a £650m plan to cut rail journeys between Glasgow and Edinburgh by 10 minutes, which include transformation of Queen Street Station

The major investment is the latest stage of a programme to electrify the country's rail network.

It will see the introduction of longer electric trains, better reliability and increased capacity for passengers travelling between Queen Street and Edinburgh via Falkirk High line, with the bonus of wifi on all trains by the end of next year.