SNP and Green ministers have been warned they are “all rhetoric and no delivery” in tackling the climate emergency after being threatened with legal action.

The Scottish Government is being threatened with legal action unless it publishes full details of the environmental impact of policies contained in its infrastructure investment plan – amid accusations that ministers are already breaching their government’s own climate change legislation.

The Climate Change (Scotland) Act 2009 requires the Scottish Government to show how investments are in line with emissions targets.

Scotland has pledged to become net zero by 2045 and cut 1990 levels of carbon emissions by 2030.

Emissions were cut by around 50% between 1990 and 2020 meaning the same level of progress is needed in this decade alone.

The Scottish Government’s infrastructure investment plan for 2021 to 2026 outlined £26 billion of investment. But campaigners have warned that so far, no assessment has been published of the emissions these projects will produce.

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As a result the Environmental Rights Centre for Scotland (ERCS) and Good Law Project have now written to Net Zero Secretary Mairi McAllan, setting out their intention to take legal action.

Dr Shivali Fifield, chief officer at the RCS, said: “By failing to publish a climate impact assessment for its Infrastructure Investment Plan, the Scottish Government is leaving citizens in the dark, with no way to keep check on whether public money will be spent on projects that drive up carbon emissions.

“To the Government we say: show us your homework. Too many times, you have over-promised and under-delivered, and in a climate emergency, the stakes are too high for wishful thinking.”

Dr Shivali added that “effective public scrutiny” was needed to “ensure reality matches rhetoric” on environmental issues.

Meanwhile, Emma Dearnaley, legal director at the Good Law Project, said: “The Scottish Government says it is committed to reaching net zero.

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“But it’s breaching its own climate legislation that sets the emissions targets needed to get there.

“It’s one thing to make climate commitments – it’s another to deliver on them. So it’s vital we can all see if the Government’s investment plans clash with its plans to tackle the climate crisis.”

She added: “There’s no time to lose in the fight against irreversible damage from global heating.

“That’s why we won’t hesitate to bring a legal challenge if the Scottish Government doesn’t publish these crucial climate assessments.”

Scottish Conservative shadow net zero, energy and transport secretary, Douglas Lumsden, said: “This is potentially a hugely embarrassing situation for the SNP-Green Government.

“Ministers are full of rhetoric on tackling climate change, but far too often fail to put their warm words into action.

“It is a clear dereliction of duty that this assessment has not been carried out and the public is being kept in the dark. Ministers must rectify this immediately before taxpayers have to foot the bill for a costly legal challenge.”

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Scottish Labour net zero spokesperson, Sarah Boyack, said: “Once again the SNP-Green Government is riding roughshod over its own environmental pledges.

“This Government is all rhetoric and no delivery when it comes to tackling the climate emergency, but the stakes are too high for this kind of incompetence.

“We urgently need infrastructure investment to help us meet our climate goals and it is astounding that the SNP-Green government hasn’t bothered to check if their own plans meet those targets.

“It’s time for the Government to start treating this climate emergency with the urgency it deserves – and delivering on their legal obligations is the least they can do.”

Scottish LibDems climate emergency spokesperson, Liam McArthur, said: "The impact of the climate emergency is becoming more visible in Scotland year on year with new and extreme weather patterns. 

"Meantime, the effects on the Global South are even more dramatic and existential.

"Every decision our governments take must recognise the seriousness of the climate and biodiversity emergencies and be tailored to meeting our climate goals. Scotland undoubtedly needs to modernise its infrastructure, but this must be done in ways that are sustainable.

“Scotland has regularly missed its climate change targets. Ministers need to show that they are up to the challenge or lawsuits like this will be the least of their problems."

The Scottish Government has been contacted for comment.