Devon and Cornwall could see a new "state-of-the-art fleet" of intercity trains in just over three years as part of proposals put forward by First Great Western in its new franchise deal with the Department for Transport.

The new franchise will see FGW operating the Great Western route until at least April 2019.

FGW today announced Hitachi Rail Europe as the preferred supplier, subject to contract, for 29 new AT300 trains, which would increase the number of seats for customers by 24 per cent, increase train frequencies at key stations, and help speed up typical journey times from London by 5 minutes (Exeter), 6 minutes (Plymouth) and 14 minutes (Penzance). First is in the final stages of securing private financing for the deal.

The bi-mode trains would be able to run in diesel or electric mode at speeds of up to 125mph, and are similar to the new Super Express Trains that will operate on the Great Western mainline between London, Bristol and South Wales.

Key differences include higher powered engines designed to handle the track gradients in Devon and Cornwall. They will run as electric trains between London and Newbury, and are equipped with bigger fuel tanks to cater for the long distance journeys to Plymouth and Penzance.

The new trains are subject to final approval from the Department for Transport before the end of June. They would enter service from summer 2018 onwards, with the full fleet in service by December 2018, when major timetable changes will transform rail services in the region.

New trains are just one part of a wide ranging deal that has been put together by First Great Western and the DfT that will see all First Great Western trains updated and modernised by December 2018, with three million additional seats in service for customers across the network.