At least 1,000 jobs will be created at a train-building factory to be built at Longannet in Fife, Spanish firm Talgo announced today.
Construction of the 70,000 square metre plant on the former power station site is expected to take 18 months.
Talgo plans to build a range of trains and has been shortlisted for the high-speed trains contract for the HS2 line due to open between London and northern England in 2026.
It said extra jobs would be created in planning and construction of the factory, which could start within a year.
However, the plan is dependent on winning train orders.
A spokesman said: "It is all contingent on a significant order, which includes HS2 and other [British] franchises.
"There are also opportunities in Ireland and round the world.
"We envisage a process where we can be ready to ‘push the button’ on construction, the day after we receive an order.
"Our strategy is to be ‘ready to build’ the day we receive an ‘anchor client’ – in other words, a train order.
"We’d hope that this will happen within twelve months,"
An “innovation centre” will also be established at Chesterfield in Derbyshire.
The company said it would establish "true manufacturing" at Longannet using UK-sourced components, rather than assembling imported parts.
President Carlos de Palacio said: "The establishment of a manufacturing facility at Longannet is a significant part of Talgo’s future
"Longannet is the preferred location for a factory site, envisaged to employ at least a thousand people."
Talgo said it had been chosen because of its good sea, rail and road connections, and availability of skilled workers.
Components may be brought in by ship, while the firm said it would be keen to see further rail electrification to enable newly-built trains to run direct from the factory.
That suggests a possible upgrading of the single-track line past Longannet between Alloa and Dunfermline which was previously used by coal trains going to the power station.
The factory would be built on the site of the power station's coal storage yard, just west of the complex.
ScottishPower is demolishing the coal-burning power station, which closed two years ago.
Talgo has built trains for the Haramain high-speed line between La Mecca and Medina in Saudi Arabia, and high-speed trains for Spanish operator Renfe.
The news will return train building to Scotland after a gap of more than 30 years.
The last ones were built at Walter Alexander factory in Falkirk, which now makes buses as Alexander Dennis.
The announcement also marks a significant expansion for 76-year-old Talgo, whose workforce will grow by one third from the current 2,000 spread across plants in Spain, Germany, Kazakhstan, Russia and the United States.
Mid Scotland and Fife Mark Ruskell Scottish Greens MSP said: “This is excellent news for the community in West Fife – the end of the coal age can be the beginning of a vibrant, low carbon industry in central Scotland and Talgo’s commitment to 1,000 new jobs will be transformative.
“The rail infrastructure in place was key to the company choosing this site, and I’m excited to see how this can pave the way for more innovative and ambitious freight and passenger rail in Scotland.
"There has been a long standing demand for a re-opening of the Stirling to Dunfermline line to passenger services, and this could be the final piece of the puzzle.
"A passenger service could form part of Talgo’s commitment to a community legacy for the local area, whilst easing the pressure on local roads that such a large increase in employment will bring.”
Transport secretary Michael Matheson said: “This investment is a significant achievement for Scotland and yet another endorsement of our country’s attractiveness to international investors.
"Should Talgo be successful in its bid to win the contract for HS2 rolling stock, this new factory at Longannet would bring a great number of new jobs to Fife, which would be a welcome boost for the local area.
"However, the full economic impact of such an investment, and the supply chain opportunities it would bring, would be felt right across Scotland."
Paul Lewis, managing director of Scottish Government agency Scottish Development International, said the plans offered “considerable benefits” .
He said: “With our public and private sector partners, we’ve worked intensively for many months to deliver the optimum proposal and to secure Scotland and Fife as the preferred location for Talgo’s investment, so this announcement today is a great news.
“The quality and skills of the workforce in the Fife area, combined with the strength of the business environment, will help Talgo realise its vision of establishing a world-class high value manufacturing facility for the rail sector.”