The UK's "dash for gas" will be halted by the government because if unchecked it would break legally binding targets for carbon dioxide emissions, Chris Huhne, energy and climate change secretary, said on Monday evening.
"We will not consent so much gas plant so as to endanger our carbon dioxide goals," he told a fringe meeting at the Liberal Democrats party conference in Birmingham.
The number of gas-fuelled power plants is increasing rapidly because they are fast and cheap to build compared with alternatives. They also create about half the carbon emissions of coal-powered plants and have been seen as a "transition fuel", helping smooth the path to zero-carbon electricity.
Barry Neville, director of public affairs at Centrica, which owns British Gas, said: "Gas is a critical part of the fuel mix, it's a transition fuel. At this moment in time it is crucial to the UK, as is nuclear and as are renewables.
But climate change campaigners have warned that too much gas capacity is being built, meaning either the carbon budgets intended to help tackle global warming would be broken, or the gas plants would be left as stranded assets.