A new limited-stop service travelling via Shotts will improve journey times for passengers in Lanarkshire travelling to Edinburgh and for those in West Lothian travelling to Glasgow, Transport Scotland said yesterday.

The government agency also unveiled a shake-up of early-morning departures that will make it easier for passengers outside Scotland’s two biggest cities to make connections to London as part of the new timetable, starting on December 13.

Early departures from Ayr and Gourock to Glasgow and from North Berwick to Edinburgh will be brought forward by around half an hour in order to make the first connecting train.

This will enable passengers in Ayr to make a six-hour journey to London Euston, leaving at 5.10am and changing at Glasgow Central.

There will also be additional early morning and late evening services between Dumfries and Carlisle, allowing passengers to connect with trains running along the West Coast Main Line between Scotland and London.

The new timetable also includes a full half-hourly train service between Glasgow and Kilmarnock, which has been introduced following the construction of a £28.5m passing loop at Lugton, allowing 32 extra trains per day to use the line.

Many of the new trains were planned to bypass the villages of Dunlop and Kilmaurs at non-peak times as part of a move to introduce faster, limited-stop services.

However, following pressure from villagers and opposition politicians, reported in The Herald, Transport Scotland reversed its decision earlier this year, to the delight of campaigners, and agreed to include both villages in the full half-hourly timetable.

The new timetable has been amended to maintain better connections with the Stranraer ferry services, Transport Scotland said. However, campaigners who have pushed for improvements on the line said they were waiting to examine the timetable in detail to see if it lived up to the pledge.

Transport Minister Stewart Stevenson said: “We have attempted to strike the correct balance between enhancing connectivity and improving journey times and we believe these changes being introduced in December will mean even more people will have the opportunity to make the switch to public transport.”

The new service between Edinburgh Waverley and Glasgow Central will take 65 minutes, with a limited stopping pattern, and will run in addition to the current hourly service, which takes 95 minutes.

It is the first step in a package of rail improvements in the central belt worth £1bn that will eventually see journey times between Glasgow and Edinburgh cut to 35 minutes and the number of trains increased from between six and seven to 13 per hour.

The Herald revealed last month that Network Rail would pay for the Edinburgh Glasgow Improvement Programme, which includes construction of a new train/tram interchange at Gogar the electrification of 350km of track and major improvements to track infrastructure and stations, by borrowing against the asset value of the railway network.

At a transport conference in Glasgow last week, Rodger Querns, Transport Scotland’s director for the project, said it was “on budget and on schedule” revealing that the programme would create 750 new jobs and lead to the reduction of 20,000 tonnes of carbon emissions per year by replacing diesel trains with less polluting electric models.

Steve Montgomery, managing director of ScotRail, said: “I welcome these widespread enhancements, with the number of services increased and also changes to improve connections. These improvements will bring many benefits to our growing number of customers.”