Landowners in a national park are denying permission for a company to drill for hydrocarbons under their properties.
In what they dexcribe as a "legal blockade" solicitors acting on behalf of residents near the village of Fernhurst, West Sussex, in the South Downs National Park, have written to oil and gas company Celtique Energie and Energy Secretary Ed Davey to say they explicitly deny permission for the firm to drill horizontally under their properties from a proposed well on land leased from a local landowner.
Celtique Energie has put in a planning application near Fernhurst, in England's newest national park, to drill a temporary vertical well to test for oil and gas and potentially drill a horizontal well extending out from it.
Celtique Energie is not applying for permission to carry out fracking, which would require a separate planning application, but campaigners say that if the company did find gas they would not be able to run a full-scale fracking well as they would not have permission from the surrounding landowners to drill outwards horizontally to access the shale.
Marcus Adams, one of the landowners involved in the blockade, said: "People right across the country have legitimate concerns about the impact of fracking on their communities – from water contamination to air and noise pollution from heavy lorry traffic – but all this happening in a national park just doesn't bear thinking about."
He said there was a presumption that hydrocarbons existed in large parts of the country and that there must be better sites for exploiting shale gas, rather than sensitive areas such as the countryside around Fernhurst.
Campaigners say the move could be replicated across the country by communities opposing fracking, but it comes as the Government considers changing trespass laws to make it easier for companies to drill under people's homes.
Adams, a long-time Conservative voter, added: "Trespass law gives residents a chance to stand up to powerful corporations wanting to drill under their homes, but now the Government wants to take this protection away from them.
"Many Tory voters here will be baffled by a government ready to bend the rule of law and chip away at homeowners' rights to make way for the industrialisation of our beautiful countryside."
Environmental group Greenpeace launched a mass legal block against fracking in October, which now has the backing of around 25,000 people across the UK.
Greenpeace energy campaigner Anna Jones said: "As ministers' desperate charm offensive is given the cold shoulder, the Fernhurst legal blockade is likely to become a blueprint for local resistance right across the country.
"Having failed to allay people's fears about the impact of fracking, the government is now ready to stack the deck against them in the looming legal battle over shale drilling.
"With one hand ministers are bribing councils to soften opposition; with the other they're stripping away long established legal protections from homeowners. This is a very perilous path to take with the next general election just months away."
A spokeswoman for the Department of Energy and Climate Change said: "Like any other industrial activity, oil and gas operations require access permission from landowners. But there is an existing legal route by which operators can apply for access where this can't be negotiated. We're currently considering whether this existing route is fit for purpose."
A spokesman for Celtique Energie said: "The horizontal well proposed as part of Celtique Energie's planning application for a temporary exploration well west of Fernhurst will be a maximum distance of 853ft from the vertical borehole at a direction of 230 degrees, in a south westerly direction.
"Therefore the horizontal well would be located exclusively within the ownership of the land owners with whom Celtique has entered into a leasing agreement for its proposed exploration well. Furthermore the horizontal well is only an option at this stage and would be drilled on the basis of positive data from the vertical well."
Celtique chief executive Geoff Davies said the site was just one of many exploratory locations it was operating in West Sussex. If the site turned out to be a "sweet spot", the firm would like to investigate further, he said.
Asked if the company wanted the Government to change the law on trespass, Davies replied: "When it comes to operations under land – telecommunications, water pipelines, gas pipelines – many things happen under land and there have been laws put in place to allow these things.
"Hydraulic fracking takes place many thousands of feet below the land and certainly if there are ransom-strip, green-verge situations going on throughout England, this will slow up the industry and obviously delay the nation's resource extraction."