Plans for hourly Enterprise train services linking Belfast to Dublin within 90 minutes are under consideration.
A report on future investment in the flagship cross-border rail service during the next 20 years is due to be published soon. Northern Ireland operator Translink is making progress on track upgrades, a Stormont minister said.
Regional Development Minister Danny Kennedy said: “The objective of this package would be to deliver a 90-minute journey time and hourly frequency on the Enterprise service.”
Trains on the blue riband service are jointly operated by Translink and Iarnrod Eireann. The cross-border link was launched by government ministers from Dublin and Belfast in 1997.
At present, connections between Belfast and Dublin can take more than two hours.
A £12 million overhaul of trains is also envisaged once EU funding has been secured, the Department for Regional Development (DRD) added.
A consultation paper released by Mr Kennedy’s department last year on the future of the line revealed that the number of passengers using the service between Belfast and Dublin has dropped by 22% over the past decade.
That was blamed on factors including recent economic conditions, recent road infrastructure improvements and loss of passengers due to the Malahide Bridge collapse.
In 2012-13, Enterprise saw passenger growth of over a tenth, with discounted online fares and benefits such as free on board wifi continuing to prove extremely popular with customers, a Translink spokeswoman has said.
Mr Kennedy told SDLP Northern Ireland Assembly member John Dallat: “Translink and Iarnrod Eireann are liaising in order to take forward a major overhaul of the existing Enterprise trains.”
He expressed confidence that the required £12 million funding will be secured from the EU and other sources.
“When this project is complete it is expected that there will be considerable improvement to the reliability of the service as well as to the aesthetics of the trains,” the minister added.
A separate project, with expected costs of £1.2 million, to carry out critical safety work to the trains is under way and is expected to be completed next year.
Translink is considering future upgrades of the track on the Belfast to Dublin line and progress is being made on efforts to upgrade the section between Knockmore and Lurgan in Co Armagh.