Transport campaigners are calling for all new road building projects paid for under city region deals to be halted.
The sustainable transport body Transform Scotland said the projects were worsening social inequality and damaging the environment.
It said road building would "lock people into unsustainable transport for decades".
The Scottish government said the city region deals aim to deliver economic prosperity.
City Region Deals are packages of funding agreed between the Scottish government, the
UK government and local partners designed to bring about long-term strategic approaches to improving regional economies.
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There are six City Region Deals in Scotland amounting to £4.6bn in spending including £1.3bn for transport projects.
The first was signed in 2014 for the Glasgow region, followed by Aberdeen and Aberdeenshire, Inverness and Highlands, Edinburgh and South East Scotland, Stirling and Clackmannanshire, with Tay Cities agreed in 2020.
However, Transform Scotland found deal projects were developed with no carbon assessments or reference to Scotland's climate targets, and they said they uncovered a lack of transparency and data around the carbon impact of spending.
Transform Scotland has written to two Scottish Parliament committees to request that they hold an inquiry to investigate the City-Region Deals' compatibility with national commitments on equalities and carbon reduction.
It says its report 'Dirty Deals' was compiled using "extensive" freedom of information requests due to a lack of public information.
It found that £900m of the £1.3bn Scottish City-Region Deal spending on transport infrastructure was being spent on high carbon infrastructure that will "lock people into unsustainable transport for decades to come".
'Empty platitudes about net zero'
The report, published on Tuesday, said only £382m was being spent on sustainable and low carbon transport, with only the Stirling Deal committing all of its spending to low carbon projects.
Transform Scotland director Colin Howden said instead of transforming cities, local and national politicians had "instead blown the cash on a new round of road-building that will inevitably generate more traffic and higher emissions".
He said the investment could have been used to reduce inequalities by investing in public transport and in our streets rather than for road projects that "further benefit the more affluent".
Mr Howden added: "We're fed up with Scotland's political class mouthing empty platitudes about 'net zero' and 'anti-poverty' yet decade after decade making deliberate decisions to build new infrastructure that makes the country's climate failure more and more certain, and neglects to provide fairer access to transport for the country's poorest."
Transform has instead called for investment to focus on more priority measures to make buses in Scotland's cities faster and networks more extensive, more spending on safer routes to schools, and funding to boost walking, wheeling and cycling infrastructure.
High-carbon projects highlighted in the report included the £151m Cross Tay Link Road near Perth, a new £107m roundabout at Sheriffhall, Edinburgh, the A96 dualling in the north of Scotland, a £25m new road access to Aberdeen South Harbour, and a £10m Dundee Airport investment.
It pointed out the City Region Deals were "only a fraction of spending" on high carbon transport in Scotland and noted that £3bn has bee committed to dualling the A9 in the Highlands.
It criticised claims this work was for "security and safety", saying there were "far less expensive and much quicker ways" to improve this through small-scale changes rather than "building miles and miles of new roads".
It said the biggest low carbon investment was Glasgow City Council's £139m "Avenues" project to transform the city centre streetscape and public realm to make it centred on people.
Transport is the biggest source of carbon emissions in Scotland at about 36%.
Campaigners said this had not changed in three decades, so government-funded projects were important if the Scottish government commitment to a 20% reduction in car use by 2030 is to be achieved.
A Scottish government spokesperson said: "The £3.4bn Scottish Regional Growth Deal programme aims to deliver economic prosperity across the country and delivers a range of capital investments which support net zero targets, including sustainable transport measures such as active travel and rail investment."
They added that environmental and social impact assessments are undertaken into every project.