British energy firm Cuadrilla on Friday announced it was cutting back its activities at a site in south England as over 1,000 protesters prepare for a six-day "action camp".
The company, which specialises in hydraulic fracturing for shale gas, the controversial technique known as "fracking", will scale back its exploratory drilling operation at Balcombe in West Sussex due to concerns over the protest by "No Dash For Gas" campaigners.
"After taking advice from Sussex Police, Cuadrilla is scaling back operations ahead of this weekend's No Dash for Gas event," said a statement from the firm.
"During this time, our main concern is the safety of our staff, Balcombe's residents and the protesters following threats of direct action against the exploration site.
"We will resume full operations as soon as it is safe to do so."
The site has been secured with barbed wire fences but the threat of confrontation looms after the anti-fracking campaign group promised "direct action".
Police have made around 40 arrests since the demonstrations began three weeks ago.
No Dash for Gas said: "There are two stories that could emerge from Balcombe this summer.
"It could be the place that paved the way for a dirty and dangerous method of fuel extraction to tear up the country, or it could be the place where a group of ordinary people inspired the world by taking back the power.
"We are here, together with dedicated people from Balcombe, to make sure that it's the latter."
Sussex Police's Lawrence Hobbs said the force was "acutely aware of the impact that this is having on the residents of Balcombe" and urged protesters not to engage in criminal activity.
"Indeed, our engagement with Balcombe people who are protesting at the site and the vast majority of those who have travelled from further afield has been mutually rewarding and we have been able to facilitate their right to assemble and protest," he added.
Scuffles broke out on August 2 when the company finally began work on a 3,000 foot (915-metre) vertical well following a three-month delay.
Fracking involves using huge amounts of pressurised water mixed with chemicals to crack open shale -- sedimentary rock containing hydrocarbons -- to release natural gas.
It has led to an energy bonanza in the United States, but has yet to begin in Britain.
The protest has attracted celebrity demonstrators, including the daughter of Pretenders singer Chrissie Hynde and Kinks frontman Ray Davies. Natalie Hynde, 30, glued herself to her boyfriend at the site entrance.