The SNP has been accused of "delivering the worst of all words" after it emerged they are failing to meet another pledge.
In 2020, the party announced a "world-leading commitment" to reduce car mileage by 20 per cent by 2030, as part of a plan to reach net zero by 2045.
But it has since emerged that the target is expected to be missed.
Scottish Conservative shadow transport minister Graham Simpson accused the party of "hammering motorists" in policies that will not help to "meet their own targets".
The SNP has been accused of "delivering the worst of all words" after it emerged they are failing to meet another pledge
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Simpson said: "As usual, the SNP is delivering the worst of all worlds. They’re hammering motorists and neglecting road maintenance, but now admit none of that will help to meet their own targets.
“Instead of pandering to their fanatical anti-car Green partners, they should reverse their cuts to public transport and infrastructure, particularly in rural areas, and stop raising ScotRail fares so that Scots actually have options about their travel."
Meanwhile, Scottish Liberal Democrat climate emergency spokesman Liam McArthur told the Scottish Express: "Like so many key climate pledges, this is yet another target that the SNP government are failing to meet.
"For too long, the Scottish Government have relied on throwing out piecemeal schemes in the desperate hope that something will stick, rather than devising a credible and workable plan."
Scottish Labour Transport spokesperson Alex Rowley agreed, saying: “The SNP is on track to miss yet another key green target because of their woeful failure to support public transport in Scotland.
"Unreliable and overpriced public transport has left countless Scots with no options but to drive – but the SNP has hit rail passengers with a staggering 8.7 fare hike and stood idly by while bus routes collapse."
It emerged that the party were set to meet another commitment in briefing notes and analysis seen by the Scottish Daily Express.
A Transport Scotland spokesman said: "We have always been clear that reaching our target of a 20 per cent reduction in car km by 2030 will require a broad combination of interventions, including infrastructure, incentives and disincentives.
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"However, we are committed to a Just Transition, and therefore our approach will take into account the needs of those who may be less able to reduce car use, such as carers, those living with a disability, people on low incomes and in rural locations.
"We will publish a final version of our route map to achieving a 20 per cent car kilometre reduction in the coming months."