The developer signed a deal for the construction and fit-out of the plant yesterday.

It said: “The close of contract between Hitachi Rail Europe and Merchant Place Developments enables the developer to award further contracts for the build of the plant.”

Archaeological exploration work is currently being carried out on the site which will take up to four months.

Construction of the plant is then expected to start at the end of 2013, with the factory scheduled to go into production in 2016.

Up to 200 workers will be employed during the construction phase.

The factory will initially be used to build the Super Express Trains for the Great Western Main Line and the East Coast Main Line.

Geoff Hunton, Director, Merchant Place Developments, said: “We have taken the design of the plant to a detailed stage and have been in discussions with suppliers and contractors so that we are ready to move ahead with the development programme.”