Jobs and services will be cut on the Tyne and Wear Metro unless an urgent bailout is agreed, ministers have been told.
At least £10m is needed to help the network cope with the impact of the coronavirus crisis, transport chiefs say.
Passenger numbers have fallen by more than 90%, with 600,000 fewer journeys made last month.
The Department for Transport has been approached for comment.
Metro operator Nexus said the money was needed before July to plug a financial black hole.
Rescue talks began more than two weeks ago but the government has yet to confirm it will cover the losses being incurred, the Local Democracy Reporting Service said.
It is understood cutbacks could see evening and off-peak services reduced.
Councillor Martin Gannon, leader of Gateshead Council and chair of the North East Joint Transport Committee, said the government "seems reluctant" to provide the same backing it has pledged to train and bus firms.
"Metro plays a huge role in the local economy, but we urgently need the Government to confirm in writing that it will provide financial support.
"Failure to do so could lead to long-term service reductions and job losses, at a time when North East England has never needed Metro more."
Speaking to the BBC, Nexus stressed services in the short-term would not be reduced and only key workers or people making essential shopping trips should continue to use the Metro.
The system costs around £104m a year to run with income from ticket sales usually generating about £48m towards that figure.
Mr Gannon has written to Transport Secretary Grant Shapps to call for immediate confirmation of financial support.
Last week the Department for Transport said it was "working closely with Nexus to identify solutions".
It has been approached for further comment.