The UK Government announced that a total of 497 carriages for the East Coast line will be built at Hitachi Rail Europe's purpose-built factory in Newton Aycliffe, County Durham, creating 730 jobs.
The Class 800 trains will start running on the East Coast line in 2018. Hitachi is also building 369 carriages to run on the Great Western line from 2017 under a funding agreement reached in 2012.
On the East Coast line the new trains will provide significant benefits to passengers, with 19% more seats on each train, reduced journey times between Edinburgh and London, via Leeds and Newcastle, by up to 15 minutes, and improved reliability.
Today's announcement finally paves the way for the long-running Intercity Express Programme (IEP) saga to reach a conclusion. It was as far back as February 2009 that the Labour government announced that Hitachi-led consortium Agility Trains was the preferred bidder for the IEP.
But a series of difficulties meant that the final contract-award decision was delayed for some time.
The contract to deliver the carriages has been agreed with Agility Trains, a consortium of Hitachi Rail Europe and John Laing.
As well as building the new manufacturing facility at Newton Aycliffe, Hitachi will construct maintenance depots at sites including Bristol and Doncaster, and is refurbishing and upgrading depots across the Great Western and East Coast lines.
Hitachi recently announced its plans to move its global rail headquarters to the UK, further underlining the confidence in the UK economy and rail market
UK Transport Secretary Patrick McLoughlin said: "We are building a world-class rail system and the IEP is a key part of that.
"These new trains will transform rail travel between many of the great towns and cities of England and Scotland. This deal is further proof that our long-term economic plans are on track, creating jobs and breathing new life into the UK's train-building industry."
Alistair Dormer, Hitachi's global rail chief executive, said: "This is an important milestone in the delivery of Class 800 series trains for the East Coast line.
"Hitachi Rail has been working closely with the Department for Transport, train operators and passenger groups to design the new trains.
"We are delighted that the success of the programme to date has attracted interest by world-class financiers and we look forward to building these trains in our new manufacturing plant in County Durham."