Stuart McDonald MP and Jamie Hepburn MSP have received information from the company itself that the route is under threat on cost grounds and are now calling for the company to have a re-think.
Both have written to the firm in their quest to have the services retained so the town can be fully linked up to Edinburgh .
Commenting, Mr McDonald said: “Whilst we appreciate that the pandemic has placed ScotRail under financial pressure, it is unacceptable that there could be no direct route from Cumbernauld or Greenfaulds stations to Scotland’s capital city.
“These routes have proven to be popular so the level of public subsidy is relatively low compared to other routes.
"Scotrail must look at this again.”
Mr Hepburn added: “There are other options available besides cutting these popular services entirely.
"We have asked ScotRail to explore all available options before taking any drastic measures.
"Locals should continue to benefit from the connectivity they have enjoyed prior to the pandemic.
However, a ScotRail spokesperson said: “The pandemic has changed how people travel across all of Scotland and our services need to reflect that.
"That’s why we are now in the process of designing new timetables to accommodate future levels of passenger demand.
“These proposals offer more services than are running today and are a new foundation for us to build on as we continue to recover and build a greener, more sustainable railway. We are proposing a new, better performing timetable with focus on improved punctuality and reliability, which we know is a priority for our customers.
“Rail is already the most sustainable mode of public transport, contributing only one per cent of Scotland’s overall transport carbon emissions, so it’s important that everyone works together to continue to modernise the railway so that it is fit for the future.”