Campaigners have argued that rules protecting National Parks from fracking could be bypassed due to a "giant loophole".
The Government has said fracking in national parks, areas of outstanding natural beauty (AONBs) and the Broads should be refused other than in "exceptional circumstances and in the public interest".
But environmentalists warned that as ministers have indicated that developing shale gas and oil resources is in the interests of the country, the rules could allow fracking in protected areas.
Official guidance states that if proposed development for shale oil or gas would lead to substantial harm or to loss of a World Heritage Site, planners should refuse consent "unless wholly exceptional circumstances apply".
Greenpeace UK energy campaigner Simon Clydesdale said: "By introducing an exception under a vague 'public interest' case, they've created a giant loophole that could allow fracking all over these protected areas, potentially causing serious environmental damage to our unique natural heritage."
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Late sunshine here and there this evening - but more cloud for southern Scotland, northern England and Northern Ireland again.