Critics say the PM should make no move to cut subsidies until he knows how it would affect the UK’s ability to meet its Paris accord obligations

The prime minister has been urged to intervene in planned cuts to solar power subsidies as a response to the signing of the Paris agreement on climate change at the weekend.

The Department of Energy and Climate Change (Decc) is expected to announce a slashing of the subsidies for solar panels, potentially by nearly 90%, in line with a concerted push by the government in recent months to roll back green measures.

The move would be disastrous for the solar industry, businesses have warned, costing jobs and impairing the UK’s ability to meet its renewable energy targets. But a former Conservative energy minister said ministers might yet reduce the level of cuts.

In Paris on Saturday, governments including the UK signed a new global agreement on climate change, that would hold global average temperature rises to no more than 2C above pre-industrial levels, while further obliging nations to work towards a more stringent goal of a 1.5C limit. Scientists estimate warming beyond 2C is likely to mean catastrophic and irreversible impacts, while 1.5C would swamp many low-lying areas, including Pacific islands.

Amber Rudd, the energy and climate change secretary, said the UK did not yet have policies in place to meet the 1.5C goal, and its focus was on keeping under 2C of warming: “We remain committed to being as ambitious as we can, but at the moment it’s only the [policies to meet] 2C that’s operational. The 1.5C [goal], I would say, is aspirational.”

Critics pointed to the contrast between the massive subsidy cut planned and the stance David Cameron and his ministers took at the Paris climate conference. The Paris agreement was hailed by Cameron and other world leaders as a “historic step” to protecting the world from dangerous global warming.

Craig Bennett, chief of Friends of the Earth, told the Guardian that the prime minister should make no move to cut subsidies until he had asked his statutory advisers, the Committee on Climate Change, how the UK would meet its obligations under the Paris accord:“They have to do that as a priority.”

If Cameron was to be taken seriously on his commitments made at Paris, Bennett said, he would have to show support for renewable energy. The UK is already far from meeting its 2020 targets on renewable generation under EU obligations, and further moves to cut support for solar panels - which follow the slashing on onshore wind support, the cancellation of a £1bn competition for a carbon capture and storage plant, and changes to planning rules that inhibit green energy - could imperil that statutory target further.

Leonie Greene, head of external affairs at the Solar Trade Association, which represents the industry, said the government’s domestic stance was in stark contrast to its posture on the world stage.

Greene said: “The critical importance of solar power in tackling climate change came up time and again at the Paris conference. Has the British government now realised the value of backing its superb domestic solar industry within an International Solar Alliance, expected to mobilise $1 trillion of investment in solar power?”

In Paris, Greene said, the Rudd had praised solar power as a technology that could help meet emissions targets. “The post-Paris world demands accelerated domestic action. The first big decision to be taken in the post-Paris world could set the tone for some time to come.”

The government argues that solar panels are falling in price, lessening the need for subsidies. But solar companies are concerned that sudden large cuts will scare off customers and investors, and say savings could be better achieved by a more gradual descent.

Lord Barker, the Conservative former climate minister and adviser to David Cameron, said: “The draft proposals, if left unchanged, would be potentially catastrophic. But I’m increasingly confident that the intention is not to leave them completely unchanged.”

Barker, who is also president of the British Photovoltaic Association and adviser to solar company Lightsource, said: “If Decc is smart, and Rudd is smart, they’ll listen to the huge number, the thousands of consultation responses, and come back with a more thoughtful response.”

Rudd said: “I think we are making it clear on renewables. I’m clear that we remain committed to them, and we’re always going to do it at the best value for money.”