Environmental campaign group Greenpeace says it is opposed to fracking because it diverts from “real solutions”, including energy efficiency and renewables, while the effects on the environment and health remain uncertain.
It is one of a raft of international organisations which has put its name to a “position statement” on shale gas and oil, coalbed methane and fracking.
In addition to highlighting widespread concerns about potential water contamination from fracking, the statement says there is no scientific agreement that unconventional technologies will have significantly lower total greenhouse gas emissions than conventional fossil fuels.
It also says unconventional gas projects could come at the expense of cheaper and safer policies to save energy and speed up the transition to renewable energy.
It adds: “An unconventional-gas boom would be an enormous experiment on the environment and human health.”