Scottish ministers have been accused of "foot-dragging" after it emerged that the promised public consultation on fracking has been delayed until the autumn, pushing the outcome beyond the Scottish election in 2016.

The Sunday Herald understands from political sources that the Energy Minister, Fergus Ewing, is planning to tell the Scottish Parliament soon that the consultation will begin in November and run until January. This is months later than many were expecting.

The delay has been criticised by both the Scottish Greens, who oppose fracking, and by the Scottish Conservatives, who favour it. Community and environmental groups have cautiously welcomed the news, while the fracking industry has sounded neutral or kept silent.

When Ewing announced a temporary moratorium on fracking and coalbed methane developments on January 28, he promised a health investigation and a public consultation. He said he would announce the consultation "in around two months" and it would last for 12 weeks.

But the delay now means that any decision to maintain or end the moratorium is unlikely to be made before the Scottish election in May 2016. The most advanced proposals for exploiting coalbed methane at Airth near Falkirk were originally scheduled to start in 2013.

"Given the huge level of public concern, it is simply unacceptable that Scottish ministers have failed to bring forward their promised consultation by now," said the Green MSP, Alison Johnstone.

"Many people will be wondering if the SNP is trying to delay making a decision on fracking until after the next Holyrood election. We need to see the current moratorium become a permanent ban."

Scottish Conservative energy spokesman, Murdo Fraser MSP, described the moratorium as a "political fix to kick this important issue into the long grass". The fracking industry would be frustrated by the delay, he suggested.

"The SNP is clearly afraid of being out-manoeuvred on the left on this issue", he argued. "The Scottish Government needs to start showing some leadership, and stop dragging its feet."

Bill Frew, who chairs of a broad alliance of concerned community groups, pointed out that New York State in the US took two years to review health impacts before it decided on a fracking ban. "This process should take as long as is necessary," he said.

"We are concerned to ensure a thorough, independent, and detailed review process, that addresses the many unanswered questions and emerging issues in other parts of the world."

Ken Cronin, chief executive of UK Onshore Oil and Gas, said he looked forward to an announcement and would participate fully in the debate. The Grangemouth petrochemical giant, INEOS, which has recently embarked on a fracking charm offensive in Scotland, declined to comment.

The Scottish Government pointed out that its promised consultation had been supported by industry and environmentalists. "The full details of the public consultation, including the further work announced on 28 January, will be announced in due course," said a spokeswoman.