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."
More top news
Larger stores could be allowed to open beyond the current six-hour limit on Sundays under a relaxation of rules in Wednesday's Budget.
IS is now attracting women and whole families as well as young men - but will any return to carry out another 7/7?
Rain will be heavy across Scotland, parts of northern England and Wales tonight - rumbles of thunder are possible waking some of us up.