The news comes on the back of a successful pilot journey which saw passengers travel across the Forth Road Bridge fore the first time in an autonomous bus.

Now the proposed 14-mile route from Ferrytoll Park and Ride in Fife to Edinburgh Park Transport Interchange will be extended into Dunfermline city centre.

Once registered, the service featuring as fleet of five vehicles will operate a frequent timetable with the capacity for around 10,000 journeys per week.

All aboard - the first 'driverless' bus ran with passengers for the first time

Each vehicle features ‘bus captains’ who will be on board to re-assure passengers during their journey over the bridge. They are also fitted with ground-breaking sensor that enables them to run on pre-selected roads without the safety driver having to intervene or take control.

The Stagecoach trial is one of the three the company is involved in featuring the most advanced set of commercial, self-driving passenger and freight operations anywhere in the world. The others are in Cambridge and Sunderland.

The project, named CAVForth, is part funded by UK Governments Centre for Connected and Autonomous Vehicles, and will be the first registered service in the UK to use full sized autonomous buses.

Government grants announced today mean the Forth Road Bridge pilot will now run to 20 miles to include Dunfermline city centre.

Stagecoach's new autonomous bus which has travelled across the Forth Road Bridge

It will allow the project to build further on what is believed to be the world’s most complex full-sized automated bus service, and building on a pilot project that is nearing completion, with a launch planned in the spring.

The project will test and refine the commercial service model, from the current 'captained' service, with a staff member onboard, to future deployments. The additional section of the route will also take in more complex autonomous driving scenarios on busy category A and B roads, mixing with city centre traffic, making it more comparable with express style bus routes.

Carla Stockton-Jones, UK Managing Director of Stagecoach, said: “We’re very proud to be pioneers of this technology with our plans to roll out the UK’s first full-sized autonomous bus service in Scotland in the spring.

“The government funding means that we can build further on this achievement by trialling exciting new autonomous projects with our partners in Cambridge and Sunderland, and at the same time advancing the technology as we extend our Scottish bus trial to cover a longer route.”

Grant Shapps, Business Secretary said: “In just a few years’ time, the business of self-driving vehicles could add tens of billions to our economy and create tens of thousands of jobs across the UK. This is a massive opportunity to drive forward our priority to grow the economy, which we are determined to seize.

“The support we are providing today will help our transport and technology pioneers steal a march on the global competition, by turning their bright ideas into market-ready products sooner than anyone else.”

Last month, the first passengers journeyed across the Forth Bridge in an autonomous bus.

Until now, only project team members had been able to trial the service.

Route for new ‘driverless bus’ expands in Fife with Government grant