MPs on Wednesday voted in favour of the use of fracking to extract shale gas under national parks, weakening a decision against fracking in national parks made earlier this year and giving shale gas explorers access to more resources.
Britain is estimated to have substantial amounts of gas trapped in underground shale rocks and Prime Minister Cameron has pledged to go all-out to extract these reserves, to help offset declining North Sea oil and gas output.
But the use of fracking, a process whereby water, sand and chemicals are injected to open up the shale rocks and release the trapped gas is opposed by environmental campaigners.
Britain imposed a ban on fracking inside national parks in January under the Conservative-Lib Dem coalition government, in a concession to the Labour Party which had called for tighter controls to be written into law.
MPs, who supported the rule change with a slim 37-vote margin, decided to loosen this rule on Wednesday by allowing shale gas explorers to undertake fracking at least 1,200 metres below the surface in national parks.
The vote, which was held without a parliamentary debate, did not change a policy that bans fracking inside national parks.
Shale gas drillers will now be allowed to drill horizontally into deposits situated underneath national parks but shale gas wellheads must be located outside the protected zones.