Members of Extinction Rebellion staged a protest outside the office of Ludlow Conservative MP Philip Dunne on Saturday.
They were campaigning for Mr Dunne to speak out against plans for the £87m relief road – currently being planned by Shropshire Council, but opposed by Shrewsbury Town Council.
Around twenty protestors put up a picket fence outside Mr Dunne's constituency office on Broad Street in Ludlow.
They said they wanted the MP to 'get off the fence' over the issue – with many wearing printed facemasks of Mr Dunne for the protest.
Jamie Russell, a spokesman for Extinction Rebellion Shrewsbury, said: "As the world burns and the IPCC (Intergovernmental Panel on Climate Change) tells us that it is now 'Code Red' for humanity, we’re shocked that Philip Dunne still refuses to oppose the North West Road.
"This four-mile stretch of single carriageway will create 70,000 tonnes of CO2 for an operational saving of 350 tonnes a year.
"That means it will take two hundred years for it to be carbon neutral. We’re calling on Mr Dunne to get off the fence and show some leadership on this issue."
Marilyn Gaunt, a spokesperson for Extinction Rebellion Ludlow, said: "Mr Dunne is refusing to put pressure on Shropshire Council to cancel this disastrous scheme because he says it is “not in his constituency”.
"We know that he has pushed the Government to move forward more positively on green issues in his role as chair of the Environmental Audit Committee. However, on an issue like this, he needs to accept that the whole county, country and planet is his constituency."
Extinction Rebellion has warned about the potential costs of the development – with Shropshire Council liable for the cost of any overspend on the £87m road.
Kate Griffith, a Much Wenlock resident who joined the protest said: "This road has the potential to bankrupt the county, which is why I’m disappointed that my MP isn’t speaking up about it. Shropshire Council has already wasted millions on the Shrewsbury shopping centres fiasco and local services are being slashed all over.
"Why should we be paying for a road in Shrewsbury when Shrewsbury Town Council doesn’t even want it? I’d much rather see the money invested in public transport, libraries, or even repairing the roads we’ve already got, which are in a terrible state."
Mr Dunne was approached for comment.