Concerns have been raised that the project will only deal with transport problems along a "relatively narrow corridor"
Dublin Chamber says any delay to Metro North will cost the city jobs and investment.
The major transport project aims to carry more than 30 million passengers a year, with a trip from O’Connell Street to the airport taking just 19 minutes.
The line will then continue on to Swords, with the majority of the route planned to be underground.
Work is due to begin on the €2.4bn light rail system in 2021, and is expected to be finished six years later.
Last week, the Government announced a €7.5bn transport investment programme which included the long awaited project
Mary Rose Burke is the CEO of Dublin Chamber, and she spoke to Newstalk Breakfast about the long-planned metro system.
She argued that the Metro North is a 'critical piece of infastructure' for the city, and will help deal with traffic & congestion issues.
She observed: "I think the political decision now has been made to progress with Metro North, and any rowing back on that is damaging to credibility.
"This is a hugely important signal - to businesses, people of Dublin, people that are looking to invest or move into Dublin - that when we say we will build something, we will build it."
Edgar Morgenroth, Associate Research Professor with the ESRI, also spoke to Breakfast and voiced some reservations about Metro North.
He observed: "There's no doubt that Dublin has significant transport issues, and we definitely need to solve them with public transport investment.
"The problem that arises is that the Metro North project will deal with transport in one relatively narrow corridor.
"It will absorb a very significant amount of money that could not otherwise then be used for other projects for the rest of the city. It will not really deal with the full transport issues in Dublin."