NICOLA Sturgeon has "taken flight from reason" after cynically hardening her stance against fracking in a move that will damage the case for Scottish independence and be warmly welcomed by Vladimir Putin, a former Government advisor has claimed.

In a blistering attack, Professor Paul Younger, who was appointed to a Scottish Government taskforce to examine unconventional oil and gas extraction, said the SNP "need not be surprised when any scientist who respects the most basic norms of professional integrity" refuses to work with its ministers in future, following comments made by the party leader in the recent election campaign.

Professor Younger, who has previously been hailed by the SNP as an "energy engineering expert" and is a Fellow of the Royal Society of Edinburgh, said he was "flabbergasted" that all but one of Scotland's main parties were "trashing" an industry that would re-employ North Sea workers "in a far safer environment".

He added: "The Scottish offshore workforce will simply be abandoned to unemployment or, at best, to far less skilled, less lucrative jobs. The only real winner in all of this is Vladimir Putin, who cannot wait to add Scotland to the list of countries that will shortly come to depend on importing gas from Russia.

"I remain utterly baffled as to why a party that claims to want independence for Scotland is happy to forego jobs and indigenous energy security when both are in peril, placing Scotland in precarious dependency on England for both."

Nicola Sturgeon has said she is "highly sceptical" of fracking and come under pressure from Labour, the Greens and Liberal Democrats to order a complete ban on the controversial gas extraction method.

The First Minister elect said she would rule out fracking if there was "any suggestion" it harmed the environment - a shift Professor Younger said was an obvious "electoral tactic".

In a TV debate, the SNP leader went as far as to suggest that Scottish Government research on fracking decommissioning may have been ordered to justify a ban, saying "perhaps what we're trying to show is just how expensive and difficult it might be to do that".

Her new position contrasted sharply with public statements made by SNP ministers when a moratorium over unconventional oil and gas, to remain in place until a process of consultation and research is completed next year, was introduced early in 2015.

READ MORE: Sturgeon says she is 'highly sceptical' about fracking, as SNP faces claims of preparing to back unconventional gas

Then, energy minister Fergus Ewing said "we should never close our minds to the potential opportunities of new technologies", that a final decision would be taken with evidence as the "central foundation" and that the Government would "consider the evidence once we have it and not prejudge it before we have sought or obtained it."

Professor Younger, Rankine Chair of Engineering and Professor of Energy Engineering at the University of Glasgow, expressed dismay that "the SNP government’s brief flirtation with evidence-based policy-making has been swiftly superseded by policy-based evidence making".

He said that "posturing and stalling" from the SNP had led already driven away investment and said that Ineos, the owner of the Grangemouth industrial plant which still hopes to be granted permission for fracking, may pull out of the country in the years to come.

READ MORE: Sturgeon says she is 'highly sceptical' about fracking, as SNP faces claims of preparing to back unconventional gas

Professor Younger added: "Nicola Sturgeon's statement that 'if there is any suggestion at all it harms our environment there will never be fracking allowed in Scotland' is clear evidence of the ongoing flight from reason. Obviously there have already been plenty of suggestions to this effect, mainly by people who have no qualifications to comment on these technical matters – but the real issue, which was fully addressed in the 2014 report, is whether these 'suggestions' stand up to scientific scrutiny. They don’t."

The Tories remain the only Holyrood party to back fracking, a process that sees a mix of water, sand and chemicals pumped deep underground to fracture shale rock and release gas. Professor Younger last week published a paper which he said proved that one of the primary concerns of environmentalists, the potential for ground-water contamination, is a "red herring" in Scotland.

The panel he was part of, which issued its report for the Scottish Government in 2014, concluded that shale gas could be safely extracted and offer the country an economic boost.

Richard Dixon, director of Friends of the Earth Scotland (pictured above), accused Professor Younger of displaying a "contempt for democracy", saying parties were merely reflecting concerns of the public and communities. He added: "The evidence from around the world has led to plenty of countries and regions ruling out fracking and we are convinced that the current moratorium studies will come to the same conclusion here. On climate change grounds alone the world can’t possibly afford fracking to go ahead."

READ MORE: Fracking questions remain for SNP

An SNP spokesman said that a decision over whether to allow fracking would be based on "both evidence and public opinion." He added: "Unless it can be proven beyond any doubt that there is no risk to health, communities or the environment, there will be no fracking in Scotland."