The first of 23 new trains will be running by the end of next year in the opening phase of an £80 million sterling investment programme to replace Northern Ireland's rolling stock.
Diesel versions of trains which operate London's Heathrow Express service have been ordered from Spanish company CAF, it was announced today.
Some trains in Northern Ireland are almost 35 years old, and the authorities have been under fierce pressure to upgrade and modernise the rail network.
All 23 trains, which are capable of speeds of up to 90mph, are all due to be running by December 2004.
Regional development minister Mr Peter Robinson admitted that standards of passenger comfort and reliability had fallen short of what was required in Northern Ireland.
But the largest ever single investment in rolling stock had signalled the start of a new era on the railways.
"Investment in our public transport infrastructure is long overdue, and I see this as just the beginning of our efforts to revitalise rail travel in Northern Ireland," he said.
PA