Liz Truss has scrapped the ban on fracking in England from today, which means gas could be flowing within six months.
The new Prime Minister told MPs she was ending the moratorium on shale gas extraction - in breach of a 2019 Tory manifesto commitment.
In a statement to MPs on plans to curb the energy crisis, Ms Truss also gave the green light to a wave of new oil and gas exploration in the North Sea, as well as a drive for clean power including nuclear, wind and solar.
She said: "We will end the moratorium on extracting our huge reserves of shale - which could get gas flowing as soon as six months - where there is local support for it."
But there was nothing on efforts to help households save energy through insulation and other efficiency measures that can permanently cut gas use and bills - a key ask from green groups and anti-poverty campaigners.
Fracking involves extracting gas from rocks and breaking them up with water and chemicals at high pressure.
A moratorium was imposed on the controversial process in November 2019 after experts said it was not possible to accurately predict the probability or magnitude of earthquakes linked to the process.
The Tory manifesto in 2019 promised: “We will not support fracking unless the science shows categorically that it can be done safely.”
Ms Truss' new Chancellor Kwasi Kwarteng said only six months ago that fracking was not the answer to the energy crisis.
But the energy bills crisis triggered by Russia's invasion of Ukraine has ramped pressure on the UK Government to secure Britain's energy supply.
The Government is expected to publish a report from the British Geological Survey, who examined possible effects, such as the risk of tremors.
Despite the wording of this report, commercial fracking will happen “in parallel” with exploratory drilling, No10 said.
The move has enraged critics, who warn it harms efforts to battle climate change and won't save households money on their bills.
Keir Starmer said fracking will drive a "coach and horses" throughout the UK's efforts to fight the "looming climate crisis", the Labour leader has said.
He told the Commons: "The Prime Minister is right to recognise that immediate support needs to be combined with longer term action.
"But I'm afraid fracking and a dash of gas in the North Sea will not cut bills, nor strengthen our energy security, but they will drive a coach and horses throughout efforts to fight the looming climate crisis."
He warned that squeezing every drop out of fossil fuel reserves would be "devastating" for the planet - and "totally unnecessary".
Business, Energy and Industrial Strategy Committee chairman Darren Jones said: "Whilst welcome, this is a temporary response to an urgent issue.
"If the Government is serious about tackling the energy crisis ministers will quickly follow through with announcements on home insulation - the permanent solution to reducing energy bills - and further expansion of renewable energy.
"Fracking and new drilling in the North Sea will do nothing to change prices and won’t produce new energy for at least half a decade.
"They will however make it much harder for the U.K. to hit its net zero targets to tackle climate change.”
Rosie Rogers, Head of oil and gas for Greenpeace UK, said: "Millions of people will breathe a sigh of relief at being pulled back from the brink of fuel poverty, but it's the fossil fuel giants that will be uncorking the bubbly."
She added: "This approach will not create the energy future we need, with insulated homes and efficient heating powered by cheap renewable energy, but it may break the decarbonisation promises made to the public, on the back of which this government was elected.”
Mike Childs, head of science, policy and research at Friends of the Earth, said: “The government’s energy plan is farcical in its detachment from reality. It does nothing to tackle the root cause of the energy crisis – our reliance on costly, polluting fossil fuels – and only lines the pockets of the oil and gas companies driving the cost of living and climate emergencies. "
But shale gas firm Cuadrilla argued that the move would help maximise the UK's domestic energy supply, reducing reliance on Russia.
Cuadrilla CEO Francis Egan said: "The last few months have highlighted the risks associated with ever increasing reliance on expensive, uncertain, and higher emission gas imports.
"Without the strong measures set out today, the UK was set to import over two thirds of its gas by the end of the decade, exposing the British public and businesses to further risk of supply shortage and price hikes down the line."
