Ministers must set a specific target for restricting carbon emissions from power generation, businesses have said.
The plea is made in an open letter to Chancellor George Osborne signed by 50 businesses and organisations.
They want a target for how emissions should be curbed by 2030, arguing that a failure to show commitment to reducing carbon emissions may harm the economy and their commercial prospects.
Mr Osborne has outlined plans to get energy from gas beyond 2030.
Labour Leader Ed Miliband has backed a 2030 target for the power sector and the Liberal Democrats have supported a target under the Energy Bill, to be included in secondary legislation to allow flexibility.
The government's climate advisers have warned support for future gas plants without technology fitted to cut emissions is not compatible with climate change legislation and is harming investment in low-carbon power such as renewables and nuclear.
Companies and investors have joined with trade unions, environmental groups and industry bodies to warn the chancellor that support for gas power into the 2030s is undermining investment in UK electricity infrastructure.
The introduction of a carbon intensity target for the energy sector would, they say, provide investors with the long term confidence needed to transform the electricity market and promote wider economic growth.
Such a target would also be in line with recent recommendations from the independent Committee on Climate Change
The letter was signed by 50 businesses and organisations, including Microsoft, Marks and Spencer, Alliance Boots and Asda.
In it, they warn the Mr Osborne that uncertainty over the government's commitment to low-carbon power generation is harming the development of green businesses.
The letter states: "The government's perceived commitment to the low carbon transition is being undermined by recent statements calling for unabated gas in the power sector beyond 2030 and the absence of a specific carbon intensity target."
It highlights a recent report by business group the CBI, which estimates that while a third of UK growth in 2011/2012 came from green businesses, policy uncertainty could lose the UK £400m in exports in 2014/2015 alone.
"It is essential for government to provide investors with the long-term confidence they need to transform our electricity market and make investments capable of driving wider economic growth," says the letter.
Peter Young, chairman of the Aldersgate Group which co-ordinated the move, called for an end to "any political uncertainty surrounding the UK's energy future".
And Andy Atkins, executive director at Friends of the Earth, which backed the letter, said Mr Osborne's support for gas power was looking "increasingly isolated".
Asda, Aviva, British American Tobacco, EDF, Microsoft, Marks & Spencer, PepsiCo, Philips, Sky and the Co-operative are among the businesses to have signed the letter.