Cop26 has sounded the “death knell” for coal, the Prime Minister has said, as he defended the deal against charges it had been significantly watered down after last-minute concessions to China and India.

The Prime Minister said it was impossible for the UK to force big polluters to cut their emissions, but insisted that the change in wording from “phasing out” coal to “phasing down” coal did not “make that much difference”. 

But he acknowledged that the so-called Glasgow Climate Pact was “tinged with disappointment” after several of its key pledges were softened during the talks and commitments to cut emissions fell short of the aim to keep warming to 1.5C. 

Climate campaigners have said the change in language, which came after an 11th-hour deal between China and India, will allow countries to continue using coal indefinitely. 

“The conference marked the beginning of the end for coal,” said Mr Johnson. “For the first time ever the conference published a mandate to cut the use of coal power. The conference has sounded the death knell for coal power.” 

Mr Johnson said it was impossible for the UK, which acted as the broker for talks in Glasgow, to force other nations to cut their emissions. 

“We can lobby, we can cajole, we can encourage, but we cannot force sovereign nations to do what they do not wish to do,” he said. 

He said that the Cop26 summit, which ended on Saturday night in Glasgow, had reached a “game-changing agreement” and rejected suggestions that it had kicked the can down the road. 

‘We haven’t cracked this thing’

The deal means the 196 countries will be expected to return next year with new plans to cut emissions before 2030, in order to keep global warming “well below 2C”. 

Pledges brought to the summit by world leaders for emissions cuts by 2030 will put the world on track for around 2.4C, analysts have warned. 

The UK Government had made the aim of the Glasgow summit to keep the world on track for warming of just 1.5C, the preferred aim of the Paris Agreement, which Mr Johnson insisted on Sunday night had been achieved. 

“Cop26 was never going to be able to halt climate change,” he said. “That was never on the cards.”

He said it would be “a fatal mistake would be to think we’ve cracked this thing”.

But he said that the mention of coal and fossil fuels in the deal was a historic first, and would prove to be “the beginning of the end” for coal. 

“Whether the language is phase down or phase out doesn’t seem to me as a speaker of English to make that much of a difference. The direction of travel is pretty much the same,” he said.

China and other major polluters had pushed back on key elements of the talks throughout the two weeks of negotiations.