A former minister has told the Executive it is facing a "stark choice" if it wants to save Northern Ireland's public transport system.
It was warned this week that Translink is facing "imminent and serious collapse" due to funding cuts and a deficit approaching £30m.
Yesterday a trade union representing workers threatened strike action if jobs are put at risk because of the operator's financial crisis.
Danny Kennedy served as Regional Development Minister from 2011 to 2015, and had previously warned about budget cuts.
He said yesterday: "In my time as minister, it was clear that insufficient money was released by the Executive to keep services going. Translink had to fall back on their reserves, which are now almost gone.
"This new Executive faces a very stark choice. If we are to maintain our public transport system, then it is essential that the necessary funds are released.
"The parties are all aware of that. I was succeeded as minister by the DUP's Michelle McIlveen and Sinn Fein's Chris Hazzard. Their parties know that the historic underfunding of infrastructure must be addressed.
"Infrastructure, like other departments, has always played second fiddle to health and education. I understand that, but people still expect services in terms of public transport, street lighting, grass cutting and road maintenance - and all those services have been impacted by a lack of funding.
"This is a key issue not just for Nichola Mallon, but for the entire new Executive."
A Translink spokesperson stressed that, due to an agreement with the Department for Infrastructure (DfI), commitments have been made to ensure adequate funding is in place to maintain its services.
According to its latest accounts for the year ending March 31, 2019, the Northern Ireland Transport Holding Company (NITHCo), which runs Translink, employs 4,202 workers.
Trade union Unite represents the majority of Translink's drivers, engineers and inspectors.
Unite official Davy Thompson said warnings about the company's future, which were laid bare at a meeting of Stormont's Infrastructure Committee on Wednesday, were no surprise.
"The NI Executive parties committed themselves to meeting the challenge of climate change but that verbal commitment means nothing if they allow our public transport services to collapse through underfunding," he said.
"Unite members in public transport have taken industrial action to defend public transport services in the past and we stand ready to do so again if a genuine threat to jobs and services emerges."
Peter Macklin of trade union the GMB said the Assembly needs to make a decision on Translink funding urgently.
"Not only does their indecision leave workers' lives in limbo, but dithering risks letting Northern Ireland's road system coming to a complete standstill, crippling the economy," he said.
The Translink spokesperson said the company operates under a Public Service Agreement with DfI, in which an agreement was made that funding will be made available to the operator for the provision of "socially necessary" public transport services.
"This agreement states that the funding will be maintained at such a level as to ensure that these services can be carried out by Translink and will enable it to meet going concern requirements," they added.
"Translink will continue to work with DfI to ensure sustained levels of public service obligation and concessionary fares funding going forward to maintain high quality public transport."
Translink has a fleet of 1,400 buses and trains and runs 12,500 services daily.
The company has struggled for years, attempting to manage unprofitable routes and severe budgetary constraints.
At one stage the firm was losing an estimated £13m every year running rural bus services, leading to Translink warning that such routes could be scrapped altogether.