NICOLA Sturgeon is under pressure to tell voters before next May's Holyrood election whether she intends to allow fracking in Scotland, after she confirmed that a timetable for a long-awaited public consultation will be published within weeks.

At First Minister's Questions, she faced criticism from Labour, Conservative and Green MSPs over her approach to unconventional oil and gas, eight months on from the Scottish Government calling a moratorium on new developments and promising that further research and a consultation would take place ahead of a final decision.

While she confirmed that a timetable would be published by October 10, she suggested that the new research had not yet begun. As the Government had stated that a consultation would take place after evidence gathering, it appears highly unlikely that the process will be complete in time to inform manifestos ahead of next May's vote.

Green co-convenor Patrick Harvie, who criticised for government for refusing to answer more than a dozen questions from MSPs over its moratorium over several months, said voters should be told what policy the SNP would pursue.

He said: "Of course there's a place for consultation, but the facts are clear in Scotland and across the world - we have far more fossil fuel than we can afford to burn if we're serious about climate change. Communities across Scotland have a right to know, well before next year's election, what policy the SNP will pursue if they are re-elected."

Since the moratorium was called, the Scottish Government has refused to address a series of concerns from MSPs over what the moratorium means in practice. It remains unclear whether test drilling for fracking is covered, with chemical giant Ineos keen to push ahead with plans to explore shale gas reserves in the Grangemouth area. John Wilson, the independent MSP who has seen his own questions ignored for months, said this week that ministers' refusal to answer questions was "simply unacceptable".

The SNP has also been criticised from within its own ranks for omitting underground coal gasification, a separate process that sees coal seams set alight underground and gas extracted, from its moratorium. A grassroots SNP members' group was set up this week and is aiming to persuade the leadership to take a tougher stance.

Sarah Boyack, Labour's spokeswoman for environmental justice, accused Ms Sturgeon of hiding behind the evidence gathering process to get her party through the election. Ms Boyack called for her to back her party's position of delivering a 'triple lock' which would include holding local referendums before any fracking development is allowed.

She said: "The First Minister and her Scottish Government has yet again refused to say when they will finalise a principled decision on fracking. When the consultation is launched, it must deal with all forms of unconventional gas, consult on the role of local communities in the planning process, and be transparent so the public has absolute confidence in the process. The First Minister should get the ball rolling now and release details of meetings with industry her government has held to date."

Murdo Fraser, the Conservative MSP who supports fracking, called for Ms Sturgeon to listen to the scientific evidence, pointing out that an expert panel set up by her Government had already concluded that fracking could be carried out safely.

Ms Sturgeon said the fact that she had been attacked by both pro and anti-fracking MSPs illustrated the "sensible approach" she was taking.

"We do not yet have the environmental, health and public consultation information on which to base a reasonable, precautionary, sensible judgment," she added.