NICOLA Sturgeon was yesterday challenged to abandon her government’s controversial research into fracking in Scotland and declare an outright ban.

Scottish Green co-convener Patrick Harvie threw down the gauntlet at his spring conference, saying Holyrood needed more Green MSPs to push the SNP “beyond its comfort zone”.

He said only the Greens had shown clear, consistent opposition to fracking, with Labour first backing local referendums on whether to drill, then a ban, and the LibDems supporting fracking when in power at Westminster, then U-turning this week to back a ban.

The SNP Government last year declared a moratorium on fracking, but recently ordered research on its environmental, health and economic aspects, as well as a study into how any future fracking operations could be decommissioned.

Addressing around 200 delegates in Edinburgh, Harvie said: “Greens are here to give absolute crystal clarity. It’s a clarity we’re not getting from the SNP. If Nicola Sturgeon is to be taken seriously when she said on Thursday ‘it ain’t going to happen’, then why on earth do we need to spend time and money researching the implications of going ahead with these technologies or how to clean up the mess afterwards?

“If the SNP are clear that fracking ain’t going to happen in Scotland, I challenge them now to cancel that programme of consultation and research, put the money into something worthwhile instead, and have an immediate, permanent, full ban on fracking and all unconventional gas.”

The Glasgow MSP added the other parties were also committed to extracting as much oil and gas from the North Sea as possible, despite the threat to climate change.

“We have no sympathy for those simply trying to outflank one another on fracking while continuing a relentless pursuit of other fossil fuels, which we know are unsafe,” he said.

Fracking, or hydraulic fracturing, is the process of releasing methane gas from deep underground by pumping water and chemicals at high pressure into shale beds.

Central Scotland has large areas of shale and Ineos, the petrochemical giant that runs the Grangemouth refinery, is keen to use the technology north of the border.

A recent Scottish Government-commissioned report said fracking could be done safely, but critics say it can cause pollution, contaminate groundwater, and adds to climate change.

Despite its own research backing the technology, the SNP has put off a decision on whether to allow it until after the election, while it gathers further evidence. This has fuelled claims that ministers, seeing a possible way to raise millions in tax, secretly plan to allow fracking once the moratorium ends.

The issue shot up the political agenda last week when Kezia Dugdale said Labour would ban fracking and challenged Sturgeon at First Minister’s Questions to make her position clear.

Sturgeon replied: “Let me put it simply: there will be no fracking in Scotland because there is a moratorium on fracking. That is what a moratorium means – it ain’t allowed to happen.”

However, she did not address what lay beyond the moratorium.

To widespread ridicule, the Scottish LibDem leadership announced yesterday their manifesto would also include a ban on fracking - just a week after LibDem members voted to allow it.

The Greens have registered the description “Ban Fracking Now” with the Electoral Commission, meaning the phrase can appear next to party’s name on ballot papers.

In digs at the SNP’s perceived lack of radicalism, the party has also registered Scotland Can Be Bolder and A Bolder Parliament, a Better Scotland.

The party is hoping to win its largest ever haul of candidates in May: one from each of the eight regional lists, and possibly two from Glasgow, Lothian and the Highlands & Islands.

Harvie said the SNP’s timidity in office, exemplified by ambiguity over fracking and “tweaking” the council tax, was helping to make the case for more Green MSPs and a bolder parliament.

He said: “It’s astonishing that the SNP seem determined to prove that our demand for a bolder Holyrood is an urgent one, but I thank them for making that case so clearly."

A number of list candidates attacked what they called the “SNP’s council tax”.

Andy Wightman said it was a discredited Tory relic, while Sarah Beattie-Smith was cheered for declaring: “The SNP’s council tax must go!”

Ross Greer said the Greens would push for a 50 per cent increase in carer’s allowance after the election and Kirsten Robb said they could create 204,000 green energy and technology jobs by 2035.

A Scottish Government spokesman said: “Research has been commissioned on the environmental, climate change, public health and economic issues associated with unconventional oil and gas to fully inform public debate. No fracking can or will take place while the Scottish Government’s moratorium on unconventional oil and gas remains in place.”