Rolling back policies designed to support green technology risks sending a "worrying signal" to businesses, the head of the Confederation of British Industry (CBI) has said.
Since the general election, ministers have announced curbs to solar and onshore wind subsidies, abandoned the Green Deal home energy saving loans scheme and axed plans to make all homes zero carbon by 2016.
However, the leading business group's director general John Cridland said the green economy was "brimming with opportunity" and that businesses wanted to be part of the solution to climate change, but he warned the Government was sending mixed messages on backing for energy efficiency and renewable power.
Cridland was speaking at an event organised by Think tank Green Alliance, alongside former US vice president and climate campaigner Al Gore, in the build-up to crucial climate talks in Paris later this year, where it is hoped a new global treaty to tackle rising temperatures will be agreed.
He said: "The green economy is an emerging market in its own right, brimming with opportunity, and the UK has built up real credibility on climate leadership and low carbon investment. Yet, with the roll-back of renewables policies and the mixed messages on energy efficiency, the Government risks sending a worrying signal to businesses.
"We need all countries to pull in the same direction at the Paris Summit to give firms the certainty and confidence they need to invest in the green economy for the long run. Politicians and negotiators should be confident that business is behind them in securing a lasting climate deal."
Gore urged the UK to support an ambitious international agreement in Paris and return to its global leadership position on climate change .
"The United Kingdom's historic legacy of leadership on the most important moral issues faced by humanity, including the climate crisis, is long and has been recognised with respect by the community of nations," he said.
"It is time for the UK Government to honour and live up to that legacy and return to its global leadership position, domestically and abroad, by supporting an ambitious international agreement in Paris that unleashes the power of the private sector to create a global clean energy economy."
Green Alliance said the UK was ahead of the world on bringing down the cost of onshore wind, phasing out coal and had an enviable level of agreement between businesses and campaigners on the need to maintain momentum towards a low carbon economy.
Green Alliance director Matthew Spencer said: "To build on these advantages, the Government needs to clear up the confusion about what it is trying to achieve for the UK energy system, ahead of the Paris conference."