The government is planning to weaken seismic activity standards at fracking sites in a bid to encourage drilling for natural gas, it has emerged, days after the release of a major report calling for huge cuts in greenhouse gas emissions to avoid catastrophic climate change.

The move would mean communities close to fracking sites may have to put up with more powerful earth tremors as a result of the drilling.

In a letter sent to Conservative MP Kevin Hollinrake in July, energy minister Claire Perry said the traffic lights system (TLS) the government currently uses to issue alerts for seismic activity is “set at an explicitly cautious level but, as we gain experience in applying these measures, the trigger levels can be adjusted upwards without compromising the effectiveness of the controls”.

The softer stance would mean fracking would not have to be stopped in the event of smaller tremors, it continues, according to Greenpeace’s investigative unit, Unearthed, which has seen the letter.

Current rules force workers to down tools following quakes measuring above 0.5 magnitude on the Richter scale.

In April 2011, drilling firm Cuadrilla caused a magnitude-2.3 earthquake, followed by a magnitude-1.5 quake the following month, while undertaking exploratory fracking work at a site in Lancashire.

No drilling has taken place since, but the company is now poised to begin drilling for the first time since the incident. Activity is tentatively scheduled to begin this week at their Preston New Road site.

In its 2017 manifesto, the Conservative party called for a US style fracking “revolution” in the UK, to reduce imports of foreign natural gas. It is the only large political party supporting the practice, with the Labour Party, Liberal Democrats and the Greens all opposed.

Fracking has already been banned by the devolved governments in Northern Ireland, Scotland and Wales, leaving England as the only place it can legally take place.

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Mr Hollinrake, MP for the Thirsk and Malton constituency in North Yorkshire, has supported fracking if well regulated.

But he declined to back the government’s proposal, claiming it was premature, Unearthed reported.

“At this point in time I think we need to know a lot more before I’d support that position. The Traffic Light System is there for a reason,” he said. “To be fair to this government and the responsible approach I think we do take to oil and gas exploration, we haven’t fracked for seven years as a result so clearly we do take this seriously.”

Claire Stephenson from Frack Free Lancashire said: “This move can only be beneficial to the fracking industry and not to local communities who are being forced to endure this technology. The fact that they are already looking to change the safety levels to industry’s favour suggests fracking will likely cause seismic events.”

Kate Blagojevic, Greenpeace’s head of energy and climate, said: “Given that earthquakes were one of the reasons that led to a seven-year hiatus in fracking, it’s understandable that the government want to boost their pet project by diluting the standards on protection from seismic activity.”

Last week, as a last minute injunction delayed Cuardilla’s fracking programme, Ms Blagojevic told The Independent: “Millions have been spent on policing to shield the frackers from resistance in those communities, and protesters have been sent to prison for trying to protect those communities and the planet. The government should take heed, stop forcing fracking on a reluctant nation and start backing renewables now.”