Govanhill is among the areas which would be affected by the M74
Green and Socialist MSPs are uniting to oppose plans to complete the five-mile "missing link" stretch of the M74 motorway.
The parties are joining local campaigners in their fight to stop the project, which is estimated to cost between £350m and £500m.
They are also calling for a public inquiry to be launched into the proposals for a three-lane road, which will join the M74 in South Lanarkshire to the M8 at Kingston in Glasgow.
Green and Socialist MSPs will join local campaigners to stage a demonstration outside Glasgow City Chambers on Monday - the last day that objections to the scheme can be lodged.
They are encouraging local people to lodge last-minute objections to the proposals.
Scottish Socialist Party MSP Rosie Kane said: "We are asking for a public inquiry to bring people on board.
"We are asking for a democratic look at this and getting the communities involved to shape their own community in relation to their needs."
Ms Kane - who started on the path towards her political career by protesting against the M77 roads plan to the south of Glasgow - lives in Govanhill, one of the areas to be affected by the M74 project.
She said it was "completely wrong" to think that the motorway would reduce traffic in the surrounding areas.
It is an obscenity that half a billion is going to be spent on a slice of motorway five miles long
She also questioned the health impact of the plans and raised fears that toxic waste would be disturbed in some areas.
Similar concerns were raised by the Greens' Patrick Harvie, who was elected as a list MSP for Glasgow.
"In Glasgow particularly, where nearly 60% of households don't have access to a car, it is an obscenity that half a billion is going to be spent on a slice of motorway five miles long - that's £100m a mile," he said.
A campaign against the road has been mounted by JAM74 (Joint Action against the M74), a coalition of community, environmental and sustainable transport groups.
It wants the plans to be halted and is calling for a comprehensive study of all transport options for the area.
If those objections include a significant number from those who are directly affected by the construction of the road that makes it much more likely that there will be a public inquiry
Labour's Lewis Macdonald, who was deputy transport minister in the pre-election Scottish Executive, said there was a balance to be struck between the environmental and economic impact of such projects.
He forecast that the new link would free up local roads and pointed to a Scottish Enterprise study which suggested that the M74 would create up to 12,000 jobs.
"That is a very real and significant benefit for the people of Glasgow," he told BBC Scotland.
He said ministers would be informed of the number and nature of objections received to the plans.
"If those objections include a significant number from those who are directly affected by the construction of the road that makes it much more likely that there will be a public inquiry," he said.
However, he stressed that the policy decision to complete the motorway network had already been taken.