A cross party group of MSPs has joined with Friends of the Earth to call on the new SNP-led Scottish Executive to back an Edinburgh tram project.
Campaigners argue the new tram system would cut congestion
Costing an estimated £600m, the scheme had already received the backing of ministers and local councillors before May's election.
But in their manifesto the SNP said a £4m investment package would be better spent improving the city's bus network.
In March, £60m was allocated to begin work on the first phase of the project.
Friends of the Earth brought together MSPs and councillors from Labour, the Liberal Democrats, the Conservatives and the Greens to campaign in favour of the project, which also included a new tram link from Leith to the city's airport.
Mark Sydenham from Friends of the Earth said the SNP should listen to the voice of the majority.
He said: "In this new administration where they are having to ask for consensus for everything it's vital that we show them that there is massive consensus for the trams across all political parties with the exception of the SNP."
A spokesperson for the Scottish Executive said that ministers would outline their plans on the future of the tram project in due course.
Pressure to support the move has also come from the Edinburgh Chamber of Commerce who conducted an online poll among their members to determine the popularity of a new tram link.
The poll found that 75% were in favour with businesses calling for the construction programme to go ahead as planned.
In view of the poll's findings, the group's chief executive Ron Hewitt has called upon John Swinney, Cabinet Secretary for Finance and Sustainable Growth, to meet a delegation from the business community before taking any steps that would jeopardise the project.
He said: "The new administration has made clear that the economy is the number one priority for Scotland. We applaud this ambition.
"We are concerned, however, that the cancellation of either project will seriously inhibit the growth of the Scottish economy and the prosperity of the businesses we represent.
"We would welcome an opportunity to discuss this with Mr Swinney and his officials."