The Prime Minister is set to lift the ban on fracking as soon as next week to make Britain energy independent by 2040.
Current rules require drilling to stop if it causes tremors of 0.5 or more on the Richter scale.
Experts say the limit blocks the ability for shale gas to be exploited fully. According to the Royal Society, tremors of up to magnitude 2 are not generally felt by people above ground and fracking is not expected to cause tremors of more than magnitude 3.
It was banned in England in 2019 after new research raised fresh fears over the risk of earthquakes. Ms Truss’s plan to lift the fracking ban in England comes despite the Tory manifesto pledging not to do so unless it was scientifically proven to be safe amid concerns over earthquakes.
The Government was due to publish a British Geological Survey review into extracting shale gas on Thursday, which officials said showed more drilling is required to establish data. But Downing Street said this will now not be published until after the mourning period, with the official spokesman saying it will come “as soon as that period has concluded”.