Boris Johnson has joked about soaring temperatures from climate change being one possible reason for his removal from Downing Street this summer.
The former prime minister suggested record-breaking temperatures of 40C in July helped spark the Tory rebellion which saw him forced out of No 10.
“Climate change effects are all too real and visible even in the UK,” Mr Johnson said at Cop27 in Egypt. “Temperatures in London this July reached 40C, almost unbearable by UK standards.”
The former Tory leader added: “Perhaps even contributing, who knows, to unexpected political turmoil that we saw at Westminster at that time.”
Mr Johnson – who claimed to be “spirit of Glasgow Cop26” – also attacked net zero sceptics in the Tory party, warning against a “corrosive cynicism” about the cost of action to bring down emissions.
“There are people who have drawn the conclusion that the whole project of net zero needs to be delayed, mothballed and put on ice – that we need, for instance, to reopen coal-fired power stations and frack the hell out of the British countryside,” he said.
“We really need to tackle this nonsense head on,” said the former PM, who singled out his old Brexit ally David Frost for special criticism.
Referring to Lord Frost’s description of wind power as “medieval technology”, Mr Johnson said: “I would point out that burning oil is positively paleolithic.”
He added: “I believe that the critics of this agenda massively underestimate the ability of human race to harness the natural world and to come up with innovative zero-carbon solutions.”
Rishi Sunak is also in Egypt for the opening day of the conference – although it is unclear whether the two men will meet. The PM was accused of being dragged “kicking and screaming” to Cop27 to avoid being embarrassed by Mr Johnson.
Asked if had been worried about the possibility Mr Sunak may have not have attended Cop27, the former Tory leader said: “The PM is here. I’m glad he’s here … I think he’s on absolutely the right lines.”
Asked if Mr Sunak was wrong to push for more oil and gas in the North Sea, Mr Johnson said: “It’s right for the short-term to recognise that we’ve got a transition period.”
Saying he was attending Cop27 to warn against any “lurch” back towards fossil fuels and away from net zero, he added: “This is not the moment to go weak on net zero. This is not the moment to give in to [Vladimir] Putin’s energy blackmail.”
He said he hoped there would be “continuation” of US support for Ukraine after this week’s mid-terms, with some Republicans keen to pull financial backing in Kyiv’s struggles against Moscow.
“In Europe we always call on the Americans, intermittently, to rescue some great democratic cause … They’re doing it now. I’m just praying that that’s going to continue,” said Mr Johnson.
Asked about his relationship with Donald Trump, the former PM would not be drawn on the former president’s bid for a second term in the White House. “I wouldn’t want to blight any American politician with support,” he said.