Amber Rudd challenges Boris Johnson to state that he's not a climate change denier

'When I consider who to back as leader of the Conservative party, knowing where they stand on this issue, which is so important to me, will be absolutely central to who I support,' Energy and Climate Change Secretary says

Climate Change Secretary Amber Rudd has challenged Boris Johnson to make clear he is not a global warming denier, saying the issue would be “absolutely central” to her decision about who to back as the next Prime Minister.

Speaking at the Business & Climate Summit in London, Ms Rudd sought to allay fears that the UK will abandon policies designed to reduce greenhouse gas emissions after it leaves the European Union.

The prominent Remain campaigner also stressed that Britain would leave the EU as “the decision of the British people was clear” in last Thursday’s referendum.

Mr Johnson is one of the leading candidates to succeed David Cameron and Ms Rudd was asked whether voters should be concerned that the next Prime Minister might be someone who has previously questioned whether climate change is real.

She paused, smiled and bowed her head as some in the audience laughed and applauded the question.

But Ms Rudd, who had earlier "exclusively revealed" she would not be standing for Tory leader, then said: “When I consider who to back as leader of the Conservative party and future Prime Minister, knowing where they stand on this issue, which is so important to me and I think is so important to the whole country and to everyone here, will be absolutely central to who I support.

“And I will be very, very clear about that and very vocal in holding anybody to account on that the getting the sort of commitment that will reassure all of us.”

She also said the EU referendum had a lesson for those seeking to persuade people to act to address climate change.

“I felt that with the EU referendum last week that those of us campaigning on one side were very clear about the economic risks, but ultimately the decision was to leave and it was quite, to a large extent, an emotional one,” Ms Rudd said.

“It is incredibly important to have the right financial structures, the green investment banks, to consider how many millions or trillions need to be invested.

“But it’s also incredibly important to make the emotional argument and there is an emotional argument to be made here.

“It’s about protecting our planet, protecting our environment and making it clear, above all, we want to bequeath a planet … that we as the generation now have looked after.”

In January 2013, Mr Johnson wrote in his Telegraph column that the cold winter in Britain made him doubt climate change.

He said he was “all for theories about climate change, and would not for a moment dispute the wisdom or good intentions of the vast majority of scientists”.

“But I am also an empiricist; and I observe that something appears to be up with our winter weather, and to call it ‘warming’ is obviously to strain the language,” Mr Johnson added.

He cited Piers Corbyn, the brother of Labour leader Jeremy, as a scientist who believes the world is on the brink of a mini ice age.

“Now I am not for a second saying that I am convinced Piers is right; and to all those scientists and environmentalists who will go wild with indignation on the publication of this article, I say, relax. I certainly support reducing CO2 by retrofitting homes and offices – not least since that reduces fuel bills. I want cleaner vehicles,” Mr Johnson said.

“I am speaking only as a layman who observes that there is plenty of snow in our winters these days, and who wonders whether it might be time for government to start taking seriously the possibility — however remote — that Corbyn is right.

“If he is, that will have big implications for agriculture, tourism, transport, aviation policy and the economy as a whole. Of course it still seems a bit nuts to talk of the encroachment of a mini ice age.

“But it doesn't seem as nuts as it did five years ago. I look at the snowy waste outside, and I have an open mind.”

On Monday, Lord Greg Barker, a former Conservative climate minister who has advised Mr Johnson, insisted: “He is not a denier.

“If you look at his pedigree, his dad, his brother [Jo Johnson, science minister] … the opposition, if he starts to unstitch environmental legislation … he will be kebabbed with a steak knife over the dining room rable.”

John Sauven, director of Greenpeace, welcomed the “much needed reassurance” from Ms Rudd and also Energy Minister Andrea Leadsom, who spoke at an Energy and Climate Committee hearing on investor confidence, that the UK was still committed to taking a lead in the fight against climate change.

“But soothing words are not good enough,” he said. “Green investor confidence in the UK was shaky before Brexit because of the government’s ever changing and incoherent policies, which neither minister seem willing to get to grips with even now.

“Both ministers are willing to reassure Chinese and French investors in Hinkley and other new nuclear power stations, but renewables businesses are simply not receiving a fraction of the political or financial support as EDF and the Chinese state-owned companies.

“If the government intends to cut such a sweet deal for other new nuclear investors, there will be little cash left for any other renewable technologies and bills are likely to rise in the future.”